//Testando o código do  pauloamed
#include<bits/stdc++.h>
using namespace std;

#define MAXN 100010
#define MAXK 100
#define ppiii pair<pair<int,int>,int>

int n;
vector<int> v[MAXN];
vector<int> rv[MAXN];

int pd[MAXN];

int fullSolution(int x, vector<bool> &on){
  memset(pd, -1, sizeof(pd));

  int ans = -1;
  pd[x] = 0;
  for(int i = x; i >= 0; --i){
    if(pd[i] != -1){
      for(auto y : rv[i]){
          pd[y] = max(pd[y], pd[i] + 1);
      }
    }
    if(on[i]) ans = max(ans, pd[i]);
  }
  return ans;
}


int main(){
  int m, q; scanf("%d %d %d", &n, &m, &q);
  for(int i = 0; i < m; ++i){
    int a, b;  scanf("%d %d", &a, &b);; a--, b--;
    if(a > b) swap(a, b);
    v[a].push_back(b);
    rv[b].push_back(a);
  }

  // cout << block << endl;

  vector<vector<pair<int,int>>> bestDists(n);

  vector<bool> occour(n);
  for(int i = 0; i < n; ++i){
    vector<int> currPointers(rv[i].size());

    priority_queue<ppiii, vector<ppiii>, less<ppiii>> pq;
    for(int j = 0; j < rv[i].size(); ++j){
      pq.push(make_pair(bestDists[rv[i][j]].front(), j));
    }

    while(pq.size() && bestDists[i].size() < MAXK){
      auto x = pq.top();
      int j = x.second;
      int id = x.first.second;
      pq.pop();

      if(++currPointers[j] < bestDists[rv[i][j]].size()){
        pq.push(make_pair(bestDists[rv[i][j]][currPointers[j]], j));
      }

      if(!occour[id]){
        occour[id] = true;
        bestDists[i].push_back(x.first);
      }
    }

    for(auto &x : bestDists[i]) x.first++;
    if(bestDists[i].size() < MAXK) bestDists[i].push_back({0, i});
    for(auto x : bestDists[i]) occour[x.second] = false;
  }

  vector<bool> on(n, true);
  while(q--){
    int x, y; scanf("%d %d", &x, &y); x--;
    vector<int> currOff;

    int before = 0;
    while(y--){
      int z; scanf("%d", &z); z--;
      on[z] = false;
      currOff.push_back(z);
      if(z <= x) before++;
    }

    int ans = -1;
    for(auto z : bestDists[x]){
      if(on[z.second]){
        ans = z.first; break;
      }
    }

    if(before <= x && ans == -1) ans = fullSolution(x, on);
    printf("%d\n", ans);
    for(auto z : currOff) on[z] = true;
  }
}