//start-time: 2024-04-14 19:39:32
#include <vector>
#include <set>
#include <iostream>
#include <cassert>
#include <algorithm>
using namespace std;
using ll = long long;
const int w = 100;
void solve(){
int n, m, q;
cin >> n >> m >> q;
vector<vector<int>> gR(n);
for(int i = 0; i < m; i++){
int u, v;
cin >> u >> v;
gR[v - 1].push_back(u - 1);
}
vector<vector<pair<int, int>>> dp(n);
for(int u = 0; u < n; u++){
vector<int> val(n, -1);
set<pair<int, int>> aux;
aux.insert({0, u});
for(auto &v : gR[u]){
for(auto &[value, ind] : dp[v]){
val[ind] = max(val[ind], value + 1);
}
}
for(auto &v : gR[u]){
for(auto &[value, ind] : dp[v]){
aux.insert({val[ind], ind});
if(aux.size() > w){
aux.erase(aux.begin());
}
}
}
dp[u] = vector<pair<int, int>>(aux.begin(), aux.end());
}
while(q--){
vector<bool> c(n);
int u, y, ans = -1;
cin >> u >> y;
u--;
for(int j = 0; j < y; j++){
int a; cin >> a;
c[--a] = 1;
}
if(y < w) {
for(auto &[v, i] : dp[u]){
if(!c[i]){
ans = max(ans, v);
}
}
}
else {
vector<int> naive(n);
for(int v = 0; v <= u; v++){
naive[v] = c[v] ? -1 : 0;
for(auto &el : gR[v]){
naive[v] = max(naive[v], naive[el] + (naive[el] != -1));
}
}
ans = naive[u];
}
cout << ans << endl;
}
}
int main() {
cin.tie(0)->sync_with_stdio(0);
ll T = 1;
//cin >> T;
while(T--) solve();
return 0;
}
