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#include <cstdio>
#include <vector>
#include <algorithm>

const int max_n = 1010;
const int max_m = 3030;
const int max_k = 31;

int n, m, k;
int E[max_m][2];
int D[max_n];
std::vector<int> G[max_n];

int best_cover;
int p[max_n];

int epoch;
int elected[max_n];

int candidates[max_n];

std::vector<int> non_zero[max_k];
std::vector<int> recover[max_k];
std::vector<int> recoverN[max_k];
int CP[max_n][max_n];

bool lessThan(const int& i, const int& j) {
  return D[i] < D[j];
}

void check_cover(int found, int sum_d) {
  if (found > best_cover) {
    return; // no
  }
  if (non_zero[found].size() == 0) {
    if (found < best_cover) {
      best_cover = found;
      // Reset Candidates
      for (int i = 0; i < n; ++i) p[i] = 0;
      for (int i = 0; i < found; ++i) p[candidates[i]] = 1;
    } else {  // found == best_cover
      // Add candidates
      for (int i = 0; i < found; ++i) p[candidates[i]] = 1;
    }
    return; // yes
  }
  int nn = non_zero[found].size();
  for (int need = 0, sum = 0; need < nn && sum < sum_d / 2; ++need) {
    sum += D[non_zero[found][nn - need - 1]];
    if (need + 1 + found > k) return; // no
  }
  if (found == best_cover) {
    return; // no
  }
  // Pick first
  int v = non_zero[found][nn - 1];  
  candidates[found] = v;

  recover[found].clear();
  for (int i = 0; i < G[v].size(); ++i) {
    if (D[G[v][i]] > 0) {
      --D[G[v][i]];
      recover[found].push_back(G[v][i]);
    }
  }
  D[v] = 0;
  non_zero[found + 1].clear();
  for (int i = 0; i < non_zero[found].size(); ++i) {
    if (D[non_zero[found][i]] > 0) {
      non_zero[found + 1].push_back(non_zero[found][i]);
    }
  }
  std::sort(non_zero[found + 1].begin(), non_zero[found + 1].end(), lessThan);

  check_cover(found + 1, sum_d - 2 * recover[found].size());

  D[v] = recover[found].size();
  for (int i = 0; i < recover[found].size(); ++i) ++D[recover[found][i]];
  recover[found].clear();

  // Pick neightbours of first
  if (found + D[v] <= best_cover) {
    int nfound = found;
    int nsum_d = sum_d;
    ++epoch;
    for (int i = 0; i < G[v].size(); ++i) {
      if (D[G[v][i]] > 0) {
        elected[G[v][i]] = epoch;
        candidates[nfound++] = G[v][i]; 
        recover[found].push_back(G[v][i]);
      }
    }

    recoverN[found].clear();
    for (int i = 0; i < recover[found].size(); ++i) {
      const int u = recover[found][i];
      for (int j = 0; j < G[u].size(); ++j) {
        const int w = G[u][j];
        if (D[w] > 0 || elected[w] == epoch) {
          recoverN[found].push_back(u);
          --D[u];
          --nsum_d;
          if (elected[w] != epoch) {
            recoverN[found].push_back(w);
            --nsum_d;
            --D[w];
          }
        }
      }
    }

    non_zero[nfound].clear();
    for (int i = 0; i < non_zero[found].size(); ++i) {
      if (D[non_zero[found][i]] > 0) {
       non_zero[nfound].push_back(non_zero[found][i]);
      }
    }
    std::sort(non_zero[nfound].begin(), non_zero[nfound].end(), lessThan);

    check_cover(nfound, nsum_d);
    for (int i = 0; i < recoverN[found].size(); ++i) ++D[recoverN[found][i]];
    recoverN[found].clear();

  }
  return; // maybe
}

void compute() {
  scanf("%d %d %d", &n, &m, &k);
  epoch = 0;
  for (int i = 0; i < n; ++i) D[i] = elected[i] = p[i] = 0;
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      CP[i][j] = 0;
    }
  }
  for (int i = 0; i < n; ++i) G[i].clear();
  int sum_d = 0;
  for (int i = 0; i < m; ++i) {
    scanf("%d %d", &E[i][0], &E[i][1]);
    --E[i][0];
    --E[i][1];
    if (CP[E[i][0]][E[i][1]] == 0) {
      G[E[i][0]].push_back(E[i][1]);
      G[E[i][1]].push_back(E[i][0]);
      ++D[E[i][0]];
      ++D[E[i][1]];
      CP[E[i][0]][E[i][1]] = CP[E[i][1]][E[i][0]] = 1;
      sum_d += 2;
    }
  }
  non_zero[0].clear();
  for (int i = 0; i < n; ++i) {
    if (D[i] > 0) non_zero[0].push_back(i);
  }
  std::sort(non_zero[0].begin(), non_zero[0].end(), lessThan);
  best_cover = k;
  check_cover(0, sum_d);
  int cnt = 0;
  for (int i = 0; i < n; ++i) cnt += p[i];
  if (best_cover <= k && cnt > 0) {
    printf("%d %d\n", best_cover, cnt);
    for (int i = 0; i < n; ++i) {
      if (p[i]) printf("%d ", i + 1);
    }
    printf("\n");
    return;
  } 
  printf("-1\n");
}

int main () {
  int tests;
  scanf("%d", &tests);
  while (tests--) {
    compute();
  }
}