#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
using ll = long long;
const int N = 1e5;
int n,m,q;
vector<int> adj[N+5];
int d[N+5],qe[N+5],busy[N+5];
bool f[N+5],fbusy[N+5];
int head = 0, tail = 0;
set<pair<int,int>> largest[N+5];
int main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin >> n >> m >> q;
for(int i = 1,x,y; i <= m ; ++i){
cin >> x >> y;
adj[y].push_back(x);
}
for(int i = 1 ; i <= n ; ++i){
for(int j : adj[i]){
d[i] = max(d[i],d[j] + 1);
for(pair<int,int> j1 : largest[j])
largest[i].insert(j1);
}
largest[i].insert({d[i],i});
// sort(largest[i].begin(),largest[i].end(),[&](pair<int,int> x, pair<int,int>y){
// return x.se < y.se;
// });
while(largest[i].size() > 100) largest[i].erase((*largest[i].rbegin()));
}
// for(int i = 1 ; i <= n ; ++i){
// cout << i << ":\n";
// for(auto j : largest[i]) cout << j.fi << ',' << j.se << '\n';
//
// }
for(int i = 1 ; i <= q ; ++i){ int t,k;
cin >> t >> k;
for(int j = 1 ; j <= k ; ++j) cin >> busy[j], fbusy[busy[j]] = 1;
bool ok = false;
for(pair<int,int> j : largest[t]) if(!fbusy[j.se]){
// cout << j.fi << ',' << j.se << '\n';
cout << d[t] - j.fi << '\n';
ok = true;
break;
}
if(!ok){
head = tail = 0;
qe[++tail] = t;
f[t] = 1;
int ans = -1;
while(head < tail){
int u = qe[++head];
// cout << u << "!" << fbusy[u] << '\n';
if(!fbusy[u]) {
// cout << u << "!\n";
ans = max(ans,d[t] - d[u]);
}
for(int j : adj[u]) if(!f[j]){
f[j] = 1;
qe[++tail] = j;
}
}
for(int j = 1 ; j <= tail ; ++j) f[qe[j]] = 0;
cout << ans << '\n';
}
for(int j = 1 ; j <= k ; ++j) fbusy[busy[j]] = 0;
}
return 0;
}
