#include <bits/stdc++.h>
#define mid ((l+r)>>1)
using namespace std;
vector<int> vc[200005];
vector<pair<int,int>> nr[200005];
int B=150;
int ok[200005],dist[200005],tag[200005];
signed main(){
ios::sync_with_stdio(false);
cin.tie(0),cout.tie(0);
int n,m,q; cin>>n>>m>>q;
for(int i=1;i<=m;i++){
int u,v; cin>>u>>v;
vc[u].push_back(v);
}
for(int i=1;i<=n;i++){
if(nr[i].size()<B){
nr[i].push_back(make_pair(0,i));
}
for(auto v:vc[i]){
vector<pair<int,int>> nw;
int it1=0,it2=0;
while(((it1!=nr[i].size())||(it2!=nr[v].size()))&&(nw.size()<B)){
if(it1==nr[i].size()){
if(tag[nr[v][it2].second]){
it2++;
continue;
} tag[nr[v][it2].second]=1;
nw.push_back(nr[v][it2]);
it2++;
continue;
}
if(it2==nr[v].size()){
if(tag[nr[i][it1].second]){
it1++;
continue;
} tag[nr[i][it1].second]=1;
auto t=nr[i][it1];
t.first++;
nw.push_back(t);
it1++;
continue;
}
if(nr[i][it1].first+1>nr[v][it2].first){
if(tag[nr[i][it1].second]){
it1++;
continue;
} tag[nr[i][it1].second]=1;
auto t=nr[i][it1];
t.first++;
nw.push_back(t);
it1++;
continue;
}
else{
if(tag[nr[v][it2].second]){
it2++;
continue;
} tag[nr[v][it2].second]=1;
nw.push_back(nr[v][it2]);
it2++;
continue;
}
}
swap(nw,nr[v]);
nw.clear();
for(auto u:nr[v]) tag[u.second]=0;
}
}
// for(int i=1;i<=n;i++,cout<<"\n") for(auto v:nr[i]) cout<<v.first<<" "<<v.second<<" ";
while(q--){
int s,k; cin>>s>>k;
if(k>=150){
for(int i=1;i<=n;i++) ok[i]=1,dist[i]=-1;
while(k--){
int x; cin>>x; ok[x]=0;
}
for(int i=1;i<=n;i++){
if(ok[i]) dist[i]=max(dist[i],0);
if(dist[i]>=0){
for(auto v:vc[i]){
dist[v]=max(dist[v],dist[i]+1);
}
}
}
cout<<dist[s]<<"\n";
}
else{
vector<int> nd;
while(k--){
int x; cin>>x; nd.push_back(x);
}
for(auto v:nd) tag[v]=1;
int maxv=-1;
for(auto v:nr[s]){
if(!tag[v.second]){
maxv=v.first;
break;
}
}
for(auto v:nd) tag[v]=0;
cout<<maxv<<"\n";
}
}
return 0;
}
