#include <bits/stdc++.h>
using namespace std;
int N, M, Q;
vector<vector<int>> adj, revAdj;
vector<int> memo;
int goal;
int dp(int pos) {
if (pos > goal) return INT_MIN;
if (pos == goal) return 0;
if (memo[pos] != -1) return memo[pos];
int ans = INT_MIN;
for (int x : adj[pos]) {
ans = max(ans, dp(x) + 1);
}
return memo[pos] = ans;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
cin >> N >> M >> Q;
adj.resize(N); revAdj.resize(N);
for (int i = 0; i < M; i++) {
int a, b; cin >> a >> b; a--; b--;
adj[a].push_back(b);
revAdj[b].push_back(a);
}
vector<vector<bool>> busy(Q, vector<bool>(N, false));
vector<bool> dec(Q, false);
vector<int> T(Q);
for (int i = 0; i < Q; i++) {
cin >> T[i]; T[i]--;
int Y; cin >> Y;
for (int j = 0; j < Y; j++) {
int a; cin >> a; a--;
busy[i][a] = true;
}
if (Y < sqrt(N)) dec[i] = true;
}
vector<set<pair<int,int>>> sol(N);
for (int i = 0; i < N; i++) {
sol[i].insert({0,i});
for (int j : revAdj[i]) {
sol[i].insert({-1,j});
int cnt = 0;
for (auto x : sol[j]) {
if (cnt >= sqrt(N)) break;
cnt++;
sol[i].insert({x.first - 1, x.second});
}
}
}
for (int i = 0; i < Q; i++) {
if (!dec[i]) {
goal = T[i];
memo.clear(); memo.resize(T[i], -1);
int ans = -1;
for (int j = 0; j <= goal; j++) if (!busy[i][j]) ans = max(ans, dp(j));
cout << ans << '\n';
}
else {
bool ok = false;
for (auto x : sol[T[i]]) {
if (busy[i][x.second]) continue;
ok = true;
cout << -x.first << '\n';
break;
}
if (!ok) cout << -1 << '\n';
}
}
return 0;
}
