#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pll pair<int, int>
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define endl '\n'
const int blk=300;
int n,m,q;
vector<vector<pll>> best(100005);
vector<vector<int>> fro(100005);
vector<bool> exist(100005, 1);
vector<int> mem(100005, -1);
int slow(int x){
if(mem[x]!=-1)return x;
for(auto it:fro[x]){
mem[x]=max(mem[x], slow(it));
}
if(mem[x]!=-1)mem[x]+=1;
else if(mem[x]==-1 and exist[x])mem[x]=0;
return mem[x];
}
signed main(){
cin>>n>>m>>q;
for(int i=0;i<m;i++){
int a,b;cin>>a>>b;
fro[b].pb(a);
}
//~ for(int i=1;i<=n;i++){
//~ best[i][0]={0, i};
//~ }
for(int i=1;i<=n;i++){
// calculate best (max distance to) 300 nodes.
map<int,int> m;
m[i]=0;
for(auto it:fro[i]){
for(auto [node,dist] : best[it]){
m[node]=max(m[node], dist+1);
}
}
int cnt=0;
for(auto [node, dist]:m){
if(cnt >= blk) break;
printf("i %lld, node %lld, dist %lld\n", i, node, dist);
best[i].pb({node, dist});
cnt++;
}
}
while(q--){
int t,y;cin>>t>>y;
vector<int> blocked;
for(int i=0;i<y;i++){
int c;cin>>c;
exist[c]=0;
blocked.pb(c);
}
if(y<blk){
// go thru best[t]
for(int i=0;i<(int)best[t].size();i++){
auto [node, dist]=best[t][i];
if(exist[node]){
//~ printf("%lld best of t %lld is %lld and it exists\n", i,t,best[t][i].s);
cout<<dist<<"\n";
break;
}
if(i==(int)best[t].size()-1){
cout<<-1<<"\n";
}
}
}
else {
fill(mem.begin(),mem.end(),-1);
cout<<slow(y)<<"\n";
}
for(auto it:blocked){
exist[it]=1;
}
}
}
