#include <bits/stdc++.h>
#include <fstream>
#define endl '\n'
#define mod 1668223877717
#define INF -100000000000000000
//#define ll long long
//#define cin fin
//#define cout fout
using namespace std;
//ofstream fout("convention.out");
//ifstream fin("convention.in");
const int M = 1e5 + 5;
vector<int> v[M];
long long dist[M];
int main()
{
ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
int n, m, q;
cin >> n >> m >> q;
for(int i = 0; i < m; i++)
{
int a, b;
cin >> a >> b;
v[b].push_back(a);
}
while(q--)
{
int t, y;
cin >> t >> y;
for(int i = 0; i < y; i++)
{
int a;
cin >> a;
dist[a] = INF;
}
for(int i = 1; i <= n; i++)
{
for(auto j : v[i])
{
if(dist[j] != INF)
dist[i] = max(dist[i],dist[j]+1);
}
}
if(dist[t] == INF)
cout << -1 << endl;
else
cout << dist[t] << endl;
}
return 0;
}
