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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void canhazfast() {ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

#define N 1024
#define M 3072
#define K 30
#define no cout << "-1\n", void()

int ub;
bitset<N> used, good;
bool vis[N], necess[N];
int q[N], deg[N];
pii edges[M];
vi adj[N];

bool cmp_deg_lt(int x, int y)
{
    return deg[x] < deg[y];
}

bool cmp_deg_gt(int x, int y)
{
    return deg[x] > deg[y];
}

void edge_backtrack_opti(int i, int cnt = 0)
{
    retif(cnt >= ub);
    if (i < 0) {
        ub = cnt;
        good = used;
        return;
    }
    int u, v;
    tie(u, v) = edges[i];
    retif(used[u] || used[v]) edge_backtrack_opti(i-1, cnt);
    for (int j : {u, v}) {
        used[j] = true;
        edge_backtrack_opti(i-1, cnt+1);
        used[j] = false;
    }
}

bool edge_backtrack_check(int i, int cnt = 1)
{
    retif(cnt > ub) false;
    if (i < 0) {
        good |= used;
        return true;
    }
    int u, v;
    tie(u, v) = edges[i];
    retif(used[u] || used[v]) edge_backtrack_check(i-1, cnt);
    for (int j : {u, v}) {
        used[j] = true;
        bool res = edge_backtrack_check(i-1, cnt+1);
        used[j] = false;
        retif(res) true;
    }
    return false;
}

template<typename T>
int reuniq(T arr[], int m)
{
    sort(arr, arr+m);
    return unique(arr, arr+m)-arr;
}

void solve()
{
    int n, m, k, day, dsum = 0;
    vi vs, tmp, ans;
    vector<vi> ccs;

    cin >> n >> m >> k;
    for (int i = 0; i < m; ++i) {
        int a, b;
        cin >> a >> b;
        if (a > b) swap(a, b);
        edges[i] = {a, b};
    }
    //cerr << "--- 0\n";
    m = reuniq(edges, m);
    for (int i = 1; i <= n; ++i) adj[i].clear();
    for (int i = 0; i < m; ++i) {
        int u, v;
        tie(u, v) = edges[i];
        adj[u].pb(v);
        adj[v].pb(i);
    }
    //cerr << "--- 1\n";

    /// max deg prune
    priority_queue<pii, vpii> pq;
    for (int i = 1; i <= n; ++i) {
        deg[i] = (int)adj[i].size();
        pq.emp(deg[i], i);
    }
    fill_n(necess+1, n, false);
    while (pq.size()) {
        int u, du;
        tie(du, u) = pq.top();
        pq.pop();
        if (du != deg[u]) {
            pq.emp(deg[u], u);
            continue;
        }
        ctif(du <= k);
        //cerr << "cut " << u << '\n';
        retif(--k < 0) no;
        necess[u] = true;
        ans.pb(u);
        for (int v : adj[u]) {
            ctif(necess[v]);
            --deg[v];
        }
    }
    //cerr << "--- 2\n";
    /// fix edges
    m = 0;
    for (int i = 1; i <= n; ++i) {
        ctif(necess[i]);
        vs.pb(i);
        tmp.clear();
        for (int j : adj[i]) {
            if (!necess[j]) {
                tmp.pb(j);
                if (j > i) edges[m++] = {i, j};
            }
        }
        swap(adj[i], tmp);
        deg[i] = adj[i].size();
    }
    //cerr << "--- 3\n";

    /// hmmm
    /**retif(vs.empty() && m > 0) no;
    sort(all(vs), cmp_deg_gt);
    for (int i = 0; i < min((int)vs.size(), k); ++i) dsum += deg[i];
    retif(dsum < m) no;**/

    /// find CCs
    /**fill_n(vis+1, n, false);
    for (int i : vs) {
        ctif(adj[i].empty() || vis[i]);
        int sz = 0;
        q[sz++] = i;
        vis[i] = true;
        ccs.empb();
        for (int j = 0; j < sz; ++j) {
            int u = q[j];
            ccs.back().pb(u);
            for (int v : adj[u]) {
                ctif(vis[v]);
                vis[v] = true;
                q[sz++] = v;
            }
        }
    }
    retif((int)ccs.size() > k) no;**/

    /// edge backtracking
    ub = k+1;
    good.reset();
    used.reset();
    edge_backtrack_opti(m-1);
    retif(ub > k) no;
    day = ub;
    //cerr << "--- 4\n";
    for (int u : vs) {
        ctif(good[u]);
        used.reset();
        used[u] = true;
        edge_backtrack_check(m-1);
        used[u] = false;
    }
    //cerr << "--- 5\n";
    for (int u : vs) {
        if (good[u]) ans.pb(u);
    }
    sort(all(ans));
    cout << day << ' ' << ans.size() << '\n';
    for (int u : ans) cout << u << ' ';
    cout << '\n';
}

int main()
{
    canhazfast();

    int t;
    cin >> t;
    for (; t; --t) solve();

    return 0;
}