#include <bits/stdc++.h>
using namespace std;
int n, m, k, dg[100010], vis[100010], neig[100010], ecnt[100010], id[100010],
    a[100010], icnt;
queue<int> q;
vector<int> g[100010];
vector<pair<int, int> > vec[100010];
void check(int u, bool b) {
  for (int i = 0; i < g[u].size(); ++i) {
    int v = g[u][i];
    neig[v] = 1;
  }
  for (int i = 0; i < vec[u].size(); ++i) {
    if (neig[vec[u][i].first]) ecnt[vec[u][i].second]++;
  }
  for (int i = 0; i < g[u].size(); ++i) {
    int v = g[u][i];
    neig[v] = 0;
  }
  if (!b) return;
  ecnt[u] += k - 1;
  int acnt = 0;
  for (int i = 0; i < g[u].size(); ++i) {
    int v = g[u][i];
    if (!vis[v]) a[++acnt] = v;
  }
  for (int i = 1; i <= acnt; ++i) {
    int v = a[i];
    for (int j = i + 1; j <= acnt; ++j) {
      if (i == j) continue;
      int x = a[j];
      vec[v].push_back(make_pair(x, u));
    }
  }
}
int solve() {
  for (int i = 1; i <= n; ++i) {
    if (dg[i] < k) q.push(i);
  }
  int cnt = 0;
  while (!q.empty()) {
    int u = q.front();
    q.pop();
    check(u, dg[u] == k - 1);
    vis[u] = 1;
    id[u] = ++icnt;
    ++cnt;
    for (int i = 0; i < g[u].size(); ++i) {
      int v = g[u][i];
      if (vis[v]) continue;
      if (--dg[v] == k - 1) q.push(v);
    }
  }
  if (n - cnt >= k) {
    printf("1 %d\n", n - cnt);
    for (int i = 1; i <= n; ++i) {
      if (!vis[i]) printf("%d ", i);
    }
    puts("");
    return 1;
  }
  int mn = -1;
  for (int i = 1; i <= n; ++i) {
    if (ecnt[i] == (long long)k * (k - 1) / 2) {
      if (mn == -1 || id[mn] > id[i]) mn = i;
    }
  }
  if (mn != -1) {
    printf("2\n%d", mn);
    for (int j = 0; j < g[mn].size(); ++j) {
      if (id[g[mn][j]] >= id[mn]) printf(" %d", g[mn][j]);
    }
    puts("");
    return 2;
  }
  return -1;
}
int main() {
  int T;
  cin >> T;
  while (T--) {
    while (!q.empty()) q.pop();
    scanf("%d%d%d", &n, &m, &k);
    icnt = 0;
    for (int i = 1; i <= n; ++i) {
      vis[i] = ecnt[i] = neig[i] = dg[i] = 0;
      g[i].clear();
      vec[i].clear();
    }
    for (int i = 1; i <= m; ++i) {
      int u, v;
      scanf("%d%d", &u, &v);
      g[u].push_back(v);
      g[v].push_back(u);
      dg[u]++;
      dg[v]++;
    }
    if ((long long)k * (k - 1) / 2 > m) {
      puts("-1");
      continue;
    }
    int d = solve();
    if (d == -1) puts("-1");
  }
}
