#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ar array
#define ld long double
#define all(v) v.begin(),v.end()
const int INF = 1e18 + 10;
const int N = 2e5 + 20;
const int SQRT = 400;
int n, m, q;
int dp[N];
vector<int> g[N];
void calc(int x){
memset(dp, -0x3f, sizeof dp);
dp[x] = 0;
for(int i = x;i >= 0;i--){
for(auto u: g[i])dp[u] = max(dp[u], dp[i] + 1);
}
}
vector<ar<int, 2>> lps[N];
vector<ar<int, 2>> join(vector<ar<int, 2>> a, vector<ar<int, 2>> b){
vector<ar<int, 2>> v;
reverse(all(a));
reverse(all(b));
merge(all(a), all(b), back_inserter(v));
reverse(all(v));
while(v.size() > SQRT)v.pop_back();
return v;
}
void kurac(){
for(int i = 0;i < n;i++){
for(auto u: g[i])lps[i] = join(lps[i], lps[u]);
for(auto &[a, b]: lps[i])++a;
lps[i] = join(lps[i], {{0, i}});
}
}
int del[N];
signed main(){ios_base::sync_with_stdio(false);cin.tie(0);
cin>>n>>m>>q;
while(m--){
int a, b;
cin>>a>>b;
--a, --b;
g[b].push_back(a);
}
memset(del, -1, sizeof del);
kurac();
while(q--){
int x, y;
cin>>x>>y;
--x;
while(y--){
int t;
cin>>t;
--t;
del[t] = q;
}
if(y > SQRT){
calc(x);
int ans = -1;
for(int i = 0;i < n;i++){
if(del[i] != q){
ans = max(ans, dp[i]);
}
}
cout<<ans<<'\n';
}else{
int ans = -1;
for(auto [a, b]: lps[x]){
if(del[b] != q){
ans = a;
break;
}
}
cout<<ans<<'\n';
}
}
}
