#include <bits/stdc++.h>
using namespace std;
const int N=2e5+5;
const int oo=1e9+1;
int n,m,request,x,y;
bool IsBusy[N];
vector <int> g[N];
namespace sub1
{
int k;
int a[N],dp[N];
void dfs(int u)
{
if (!IsBusy[u]) dp[u]=0;
else dp[u]=-oo;
for (int v:g[u])
{
if (dp[v]==-1) dfs(v);
dp[u]=max(dp[u],dp[v]+1);
}
}
void solve()
{
while (request--)
{
cin >> x >> k;
for (int j=1;j<=k;j++)
{
cin >> a[j];
IsBusy[a[j]]=true;
}
for (int i=1;i<=n;i++)
dp[i]=-1;
dfs(x);
if (dp[x]<0) dp[x]=-1;
cout << dp[x] << '\n';
for (int j=1;j<=k;j++)
IsBusy[a[j]]=false;
}
}
}
int main()
{
ios_base::sync_with_stdio(NULL);
cin.tie(NULL); cout.tie(NULL);
cin >> n >> m >> request;
for (int i=1;i<=m;i++)
{
cin >> x >> y;
g[y].push_back(x);
// InDegree[x]++;
}
sub1::solve();
}
