#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
const int maxn = 1e5 + 1;
vector <int> adj[maxn], adjr[maxn];
bool blocked[maxn];
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n, m, q;
cin >> n >> m >> q;
for (int i = 0; i < m; i++) {
int a, b;
cin >> a >> b;
adj[a].push_back(b);
adjr[b].push_back(a);
}
while (q--) {
int t, y;
cin >> t >> y;
fill(blocked, blocked + n + 1, false);
for (int i = 0; i < y; i++) {
int x;
cin >> x;
blocked[x] = true;
}
vector <int> dp(n+1, -1);
for (int i = 1; i <= n; i++) {
if (!blocked[i])
dp[i] = 0;
for (auto j : adjr[i]) {
if (dp[j] != -1)
dp[i] = max(dp[i], dp[j] + 1);
}
}
cout << dp[t] << '\n';
}
}
