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//~ while (clock()<=69*CLOCKS_PER_SEC)
//~ #pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("O3")
//~ #pragma GCC optimize("Ofast")
//~ #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//~ #pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

using namespace std;

using ll=long long;
using ld=long double;
using pii=pair<int, int>;
using pll=pair<ll, ll>;
using vi=vector<int>;
using vll=vector<ll>;

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<" = "<<h<<endl; }
#ifdef LOCAL
#define _upgrade ios_base::sync_with_stdio(0);
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__);
#else
#define _upgrade ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
#define debug(...) 98;
#define cerr if(0) cout
#endif

#define pb push_back
#define mp make_pair
#define all(x) x.begin(),x.end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second

#define erase_duplicates(x) sort(all(x)), (x).resize(distance((x).begin(), unique(all(x))));

#define watch(x) cout << (#x) << " is " << (x) << endl;

#define pow2(x) ((x)*(x))
#define mod(x, m) ((((x) % (m)) + (m)) % (m))
#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))

#define REP(i, a, b) for(int i = a; i <= b; ++i)
#define REPV(i, b, a) for(int i = b; i >= a; --i)

const double m_pi = acos(-1.0);
const int int_max = 0x3f3f3f3f;
const int M7 = 1000*1000*1000+7;
const int M9 = 1000*1000*1000+9;

vector<int> tos[1009];
int deg[1009];
priority_queue<pii> promising;
int n, m, k;
int maxDepth;

int degToScore(int x) {
    if(x >= 4) {
        return x;
    } else if(x == 3) {
        return 5;
    } else if(x == 2) {
        return 10;
    } else if(x == 1) {
        return 100;
    }
    return x;
}

vector<pii> removeEdges(vector<int> vertices) {
    vector<pii> edges;
    vector<int> affected;
    // cout <<"sz(vertices) "<<sz(vertices)<<endl;
    REP(i, 0, sz(vertices) - 1) {
        int v = vertices[i];
        affected.pb(v);
        // cout << "v "<<v<<endl;
        while(sz(tos[v])){
            int u = tos[v][sz(tos[v])-1];
            // cout << "u "<<u<<endl;
            tos[v].pop_back();
            vector<int> tosu;
            REP(j, 0, sz(tos[u])-1) {
                if(tos[u][j] != v)tosu.pb(tos[u][j]);
            }
            tos[u] = tosu;
            affected.pb(u);
            --deg[u];
            --deg[v];
            edges.pb(mp(v, u));
            // cout <<"remove edge "<<v<<" "<<u<<endl;
        }
    }
    erase_duplicates(affected);
    REP(i, 0, sz(affected)-1){
        int x = affected[i];
        if(deg[x]) {
            promising.push(mp(degToScore(deg[x]), x));
        }
    }
    return edges;
}

void addEdges(vector<pii> edges) {
    vector<int> affected;
    REP(i, 0, sz(edges) - 1) {
        int u = edges[i].fi;
        int v = edges[i].se;
        affected.pb(u);
        affected.pb(v);
        tos[v].pb(u);
        tos[u].pb(v);
        ++deg[u];
        ++deg[v];
    
    }
    erase_duplicates(affected);
    REP(i, 0, sz(affected)-1){
        int x = affected[i];
        if(deg[x]) {
            promising.push(mp(degToScore(deg[x]), x));
        }
    }
}


vector<int> vCov(int depth, bool isExpress) {
    vector<int> ret;
    if(depth > maxDepth + 2) return ret;
    int pos = -1;
    int score = 0;
    while(!promising.empty()) {
        pii topEl = promising.top();
        // cout << "topEl "<<topEl.fi<<" "<<topEl.se<<endl;
        promising.pop();
        if(degToScore(deg[topEl.se]) == topEl.fi) {
            pos = topEl.se;
            score = topEl.fi;
            break;
        }
    }
    // cout << "pos"<<pos<<endl;
    if(pos == -1) return ret;
    if(deg[pos] <= 3) {
        int newPos = pos;
        int maxDeg = deg[pos];
        REP(i, 0, sz(tos[pos])-1) {
            int x = tos[pos][i];
            if(deg[x] >= maxDeg){
                maxDeg = deg[x];
                newPos = x;
            }
        }
        pos = newPos;
    }
    // cout << "pq size "<<sz(promising)<<endl;
    // cout << "will remove edges "<<pos<<endl;
    // cout << deg[pos] << " " << sz(tos[pos]) << endl;
    vector<int> active;
    active.pb(pos);
    vector<pii> edges = removeEdges(active);
    // cout << "rek "<<endl;
    vector<int> pickPos = vCov(depth+1, isExpress);
    pickPos.pb(pos);
    vector<int> pickOther = pickPos;
    if(score < maxDepth + 3) {
        if ((depth + sz(pickPos) > maxDepth) || !isExpress) {
            // cout << "second branch" << endl;
            active.pop_back();
            REP(i, 0, sz(edges)-1) {
                active.pb(edges[i].se);
            }
            vector<pii> edges2 = removeEdges(active);
            pickOther = vCov(depth + sz(active), isExpress);
            REP(i, 0, sz(active)-1) {
                pickOther.pb(active[i]);
            }
            edges.insert( edges.end(), edges2.begin(), edges2.end());
            // cout << "second branch end"<<endl;
        }
    }
    // cout << "qwe"<<endl;
    addEdges(edges);

    if (sz(pickPos) < sz(pickOther)) {
        return pickPos;
    } else {
        return pickOther;
    }
}

int main() {
    _upgrade
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    cout<<fixed<<setprecision(15);

    int t;cin>>t;

    REP(tt, 0, t-1) {
        cin>>n>>m>>k;
        maxDepth = k;
        vector<pii> allEdges;
        REP(i, 0, m-1){
            int a, b;cin>>a>>b;--a;--b;
            allEdges.pb(mp(a, b));
        }
        erase_duplicates(allEdges);
        REP(i, 0, sz(allEdges)-1){
            int a = allEdges[i].fi;
            int b = allEdges[i].se;
            tos[a].pb(b);
            tos[b].pb(a);
            ++deg[a];
            ++deg[b];
        }

        REP(i, 0, n-1){
            if(deg[i]){
                promising.push(mp(degToScore(deg[i]), i));
            }
        }
        // cout << "a"<<endl;

        vector<int> vertexCov = vCov(0, false);
        maxDepth = sz(vertexCov);
        int d = sz(vertexCov);
        if(d > k) {
            cout << "-1\n";
        } else {
            vector<int> cursed = vertexCov;
            vector<int> core;
            REP(i, 0, sz(vertexCov)-1) {
                // cout << "another"<<endl;
                while(!promising.empty())promising.pop();
                REP(j, 0, n-1){
                    if(deg[j]){
                        promising.push(mp(degToScore(deg[j]), j));
                    }
                }
                int u = vertexCov[i];
                vector<int> neighbours;
                REP(j, 0, sz(tos[u])-1) {
                    neighbours.push_back(tos[u][j]);
                }
                // if (!allCovered) {
                    vector<pii> removedEdges = removeEdges(neighbours);
                    vector<int> newCover = vCov(sz(neighbours) + sz(core), true);
                    addEdges(removedEdges);
                    // cout << "abc"<<endl;

                    if (sz(vertexCov) == sz(newCover) + sz(neighbours) + sz(core)) {
                        REP(j, 0, sz(neighbours)-1) {
                            cursed.push_back(neighbours[j]);
                        }
                    } else {
                        core.pb(u);
                        vector<int> uu;
                        uu.pb(u);
                        removeEdges(uu);
                    }
                    removedEdges.clear();
                // }
                neighbours.clear();
            }
            
            erase_duplicates(cursed);
            sort(cursed.begin(),cursed.end());
            cout << d<<" "<<sz(cursed)<<"\n";
            REP(i, 0, sz(cursed)-1) {
                cout << cursed[i]+1<< " ";
            }
            cout << "\n";
            core.clear();
        }

        REP(i, 0, sz(allEdges)-1){
            int a = allEdges[i].fi;
            int b = allEdges[i].se;
            tos[a].clear();
            tos[b].clear();
            deg[a] = 0;
            deg[b] = 0;
        }
        allEdges.clear();
        while(!promising.empty())promising.pop();
    }



    return 0;
}




/*
    __builtin_popcount count total set bits on a given integer
    (use __builtin_popcountll for long long).


*/