#include<bits/stdc++.h>
using namespace std;
vector<int>qr[100005];
vector<int>adj[100005];
vector<int>rv[100005];
int ar[100005];
int cant[100005];
int n,m,q;
int mx[100005];
int big(int x,vector<int>&v){
//cerr<<x<<":\n";
for(int i=1;i<=n;i++)mx[i]=INT_MIN,cant[i]=0;
for(auto x:v)cant[x]=1;
mx[x]=0;
int ans=-1;
for(int i=x;i>=1;i--){
//cerr<<mx[i]<<" ";
if(!cant[i])ans=max(ans,mx[i]);
for(auto v:rv[i])mx[v]=max(mx[v],mx[i]+1);
}
//cerr<<"\n";
return ans;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cin>>n>>m>>q;
for(int i=0;i<m;i++){
int s,e;cin>>s>>e;
adj[s].push_back(e);
rv[e].push_back(s);
}
for(int i=0;i<q;i++){
int t,y;cin>>t>>y;
ar[i]=t;
for(int j=0;j<y;j++){
int x;cin>>x;
qr[i].push_back(x);
}
}
for(int i=0;i<q;i++){
cout<<big(ar[i],qr[i])<<"\n";
}
}
