#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
const int maxn = 1e5 + 5;
vector<int> graph[maxn+5];
int block[maxn+5], dp[maxn+5];
vector<pair<int, int> > P[maxn+1];
signed main() {
ios_base::sync_with_stdio(false);
cout.tie(0); cin.tie(0);
int n, m, Q;
cin >> n >> m >> Q;
const int B = 105;
for(int i=0; i<m; i++) {
int a, b;
cin >> a >> b;
graph[b].push_back(a);
}
vector<int> ind(n+1, -1);
for(int i=1; i<=n; i++) {
vector<int> id;
P[i].push_back({ 0, i });
for(int &j : graph[i]) {
for(auto &[d, u] : P[j]) {
if(ind[u] == -1) id.push_back(u);
ind[u] = max(ind[u], d + 1);
}
}
for(int &u : id) P[i].push_back({ ind[u], u });
sort(P[i].rbegin(), P[i].rend());
while(P[i].size() > B) P[i].pop_back();
for(int &u : id) ind[u] = -1;
}
while(Q--) {
int T, Y;
cin >> T >> Y;
for(int i=0; i<Y; i++) {
int x;
cin >> x;
block[x] = 1;
}
if(Y >= B) {
dp[T] = 0;
for(int i=1; i<=n; i++) if(i != T) dp[i] = -1e9;
for(int i=n; i>=1; i--)
for(int &j : graph[i]) dp[j] = max(dp[j], dp[i] + 1);
int mx = -1;
for(int i=1; i<=n; i++) if(!block[i]) mx = max(mx, dp[i]);
cout << mx << '\n';
} else {
bool ok = 0;
for(auto &[d, u] : P[T]) {
if(block[u]) continue;
ok = 1;
cout << d << '\n';
break;
}
if(!ok) cout << -1 << '\n';
}
for(int i=1; i<=n; i++) block[i] = 0;
}
return 0;
}
