#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define fbo find_by_order
#define ook order_of_key
#define f first
#define s second
#define pb push_back
#define reset(a,b) memset(a,b,sizeof a);
#define MOD 1000000007
#define MID (l+r)/2
#define ALL(x) x.begin(),x.end()
#define debug(x) cout<<#x<<" = "<<(x)<<endl
#define mx 100003
#define pc(x) putchar_unlocked(x);
typedef tree<long long, null_type, less<long long>, rb_tree_tag, tree_order_statistics_node_update> pbds;
const int batas=330;
int n,m,q,u,v,t[mx],y[mx],di[mx],dp[mx],ans[mx];
vector<int>ve[mx],isi[mx],b[mx],g[mx];
vector<pair<int,int>>jauh[mx];
bool sudah[mx],ya[mx];
int sem=0;
int main(){
scanf("%d%d%d",&n,&m,&q);
for(int i=1;i<=m;i++){
scanf("%d%d",&u,&v);
g[u].pb(v);
b[v].pb(u);
}
for(int i=1;i<=q;i++){
cin>>t[i]>>y[i];
for(int j=1;j<=y[i];j++){
int x;
cin>>x;
ve[i].pb(x);
}
isi[t[i]].pb(i);
}
reset(dp,-1);
for(int i=1;i<=n;i++){
for(int j:b[i]){
di[j]=0;
}
while(jauh[i].size()<batas+10){
int ambil=-1,brp=-1;
for(int j:b[i]){
while(di[j]<jauh[j].size() && sudah[jauh[j][di[j]].s])di[j]++;
if(di[j]==jauh[j].size())continue;
if(brp<jauh[j][di[j]].f){
brp=jauh[j][di[j]].f;
ambil=j;
}
}
if(ambil==-1)break;
int j=ambil;
jauh[i].pb({brp+1,jauh[j][di[j]].s});
sudah[jauh[j][di[j]].s]=true;
di[j]++;
}
jauh[i].pb({0,i});
for(auto x:jauh[i]){
sudah[x.s]=false;
}
for(int x:isi[i]){
if(y[x]>=batas){
for(int j:ve[x])ya[j]=true;
dp[i]=0;
for(int j=i-1;j>=1;j--){
for(int k:g[j]){
if(dp[k]!=-1)dp[j]=max(dp[j],dp[k]+1);
}
}
int aa=-1;
for(int j=1;j<=i;j++){
if(!ya[j])aa=max(aa,dp[j]);
}
ans[x]=aa;
for(int j=1;j<=i;j++){
dp[j]=-1;
}
for(int j:ve[x])ya[j]=false;
}
else{
//debug(x);
for(int j:ve[x])ya[j]=true;
int aa=-1;
for(auto j:jauh[i]){
if(i==2){
// cout<<"INI "<<j.f<<" "<<j.s<<endl;
}
if(!ya[j.s]){
aa=j.f;
break;
}
}
ans[x]=aa;
for(int j:ve[x])ya[j]=false;
}
}
}
for(int i=1;i<=q;i++)printf("%d\n",ans[i]);
}
