#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], visited[maxn], processed[maxn];
vector <int> topo;
int id[maxn];
void dfs(int s) {
if (visited[s])
return;
visited[s] = true;
for (auto i : adj[s])
dfs(i);
topo.push_back(s);
}
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);
}
for (int i = 1; i <= n; i++) {
if (!visited[i])
dfs(i);
}
reverse(topo.begin(), topo.end());
for (int i = 0; i < n; i++) {
id[topo[i]] = i;
}
while (q--) {
int t, y;
cin >> t >> y;
fill(blocked, blocked + n + 1, false);
fill(processed, processed + n + 1, false);
for (int i = 0; i < y; i++) {
int x;
cin >> x;
blocked[x] = true;
}
int ans = -1;
priority_queue <pair <int, int>> pq;
vector <int> dis(n+1, -1);
dis[t] = 0;
pq.push({0, t});
while (!pq.empty()) {
int a = pq.top().second;
pq.pop();
if (!blocked[a])
ans = max(ans, dis[a]);
if (processed[a])
continue;
processed[a] = true;
for (auto i : adjr[a]) {
pq.push({id[i], i});
dis[i] = max(dis[i], dis[a] + 1);
}
}
cout << ans << '\n';
}
}
