#include <bits/stdc++.h>
using namespace std;
const int N = 1e5+5;
int n, m, q, party, mx;
vector<int> canal[N];
void dfs( int u, int cnt )
{
if( u == party )
{
mx = max( mx, cnt );
return;
}
for( int v : canal[u] )
{
dfs( v, cnt+1 );
}
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n >> m >> q;
while( m-- )
{
int s, e;
cin >> s >> e;
canal[s].push_back(e);
}
while( q-- )
{
int busy;
cin >> party >> busy;
bool vcnt[N] = {false};
while( busy-- )
{
int a; cin >> a;
vcnt[a] = true;
}
mx = -1;
for( int i=1;i<=n;i++ )
{
if( vcnt[i] ) continue;
dfs( i, 0 );
}
cout << mx << "\n";
}
return 0;
}
