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//Franciszek Witt
#include<bits/stdc++.h>
using namespace std;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
typedef long long ll;
constexpr int base = 15;
struct mst {
    vector<int> st;
    int si = 1;
    void init(int x) {
        while(si <= (2 * (x + 1)))
            si *= 2;
        st.resize(si);
    }
    void ins(int x, int y){
        y <<= base;
        y |= x;
        x += si / 2;
        st[x] = y;
        x >>= 1;
        while(x) {
            int mx = max(st[x << 1], st[(x << 1) | 1]);
            if(st[x] == mx)
                break;
            st[x] = mx;
            x >>= 1;
        }
    }
    int get() {
        return st[1] & ((1 << base) - 1);
    }
};
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t;
    cin >> t;
    REP(tt, t) {
        int n, m, k;
        cin >> n >> m >> k;
        vector graph(n + 1, vector<int>());
        vector vdeg(n + 1, 0);
        vector<pair<int,int>> edg(m);
        REP(i, m) {
            cin >> edg[i].first >> edg[i].second;
            if(edg[i].first > edg[i].second)
                swap(edg[i].first, edg[i].second);
        }
        sort(edg.begin(), edg.end());
        edg.resize(unique(edg.begin(), edg.end()) - edg.begin());
        m = ssize(edg);
        for(auto [a, b] : edg) {
            graph[a].emplace_back(b);
            graph[b].emplace_back(a);
            ++vdeg[a];
            ++vdeg[b];
        }
        mst st;
        st.init(n);
        FOR(i, 1, n)
            st.ins(i, vdeg[i]);
        debug(graph);
        vector<int> ans(n + 1), cho(n + 1);
        int roz = 0, best = n + 1, unma = m;
        function<void()> bck = [&]() {
            debug(roz, best, unma, cho, vdeg);
            if(roz > k || roz > best)
                return;
            if(unma == 0) {
                if(roz < best) {
                    FOR(i, 1, n)
                        ans[i] = 0;
                    best = roz;
                }
                FOR(i, 1, n)    //bitset ??
                    ans[i] |= cho[i];
                return;
            }
            int kto = st.get();
            debug(kto, vdeg[kto]);
            if(vdeg[kto] == 1) {    //mozna latwo liniowo
                debug("!!\n");
                int cnt = 0;
                FOR(i, 1, n)
                    cnt += (vdeg[i] == 1);
                assert(cnt % 2 == 0);
                if(roz + cnt / 2 > best)
                    return;
                if(roz + cnt / 2 < best)
                    FOR(i, 1, n)
                        ans[i] = 0;
                best = roz + cnt / 2;
                FOR(i, 1, n)
                    ans[i] |= (cho[i]) || (vdeg[i] == 1);
                return;
            }
            auto turnon = [&] (int x) {
                assert(!cho[x]);
                for(auto i : graph[x]) {
                    if(!cho[i]) {
                        --unma;
                        --vdeg[i];
                        --vdeg[x];
                        st.ins(i, vdeg[i]);
                    }
                }
                st.ins(x, vdeg[x]);
                cho[x] = 1;
                ++roz;
            };
            auto turnoff = [&] (int x) {
                assert(cho[x]);
                for(auto i : graph[x]) {
                    if(!cho[i]) {
                        ++unma;
                        ++vdeg[i];
                        ++vdeg[x];
                        st.ins(i, vdeg[i]);
                    }
                }
                st.ins(x, vdeg[x]);
                cho[x] = 0;
                --roz;
            };
            if(roz + 1 <= k && roz + 1 <= best)
            {
                turnon(kto);
                bck();
                turnoff(kto);
            }
            if(roz + vdeg[kto] <= k && roz + vdeg[kto] <= best)
            {
                debug(roz);
                vector<int> to;
                for(auto i : graph[kto]) {
                    if(!cho[i]) {
                        turnon(i);
                        to.emplace_back(i);
                    }
                }
                debug(roz);
                bck();
                for(auto i : to)
                    turnoff(i);
            }

        };
        bck();
        int ile = accumulate(ans.begin(), ans.end(), 0);
        if(best > k)
            cout << -1 << endl;
        else {
            cout << best << " " << ile << endl;
            FOR(i, 1, n)
                if(ans[i])
                    cout << i << " ";
            cout << endl;
        }
    }
}