#include <algorithm>
#include <iostream>
#include <vector>
#define pii pair <int, int>
using namespace std;
const int NMAX = 100000;
const int B = 1010;
vector <int> adj[NMAX + 1];
vector <pii> t[NMAX + 1];
int from[NMAX + 1];
int dist[NMAX + 1];
bool no[NMAX + 1];
int main(){
int n, m, q;
cin >> n >> m >> q;
for(int i = 1; i <= m; i++){
int a, b;
cin >> a >> b;
adj[b].push_back(a);
}
for(int i = 1; i <= n; i++){
vector <int> curr;
for(int vec : adj[i]){
for(pii x : t[vec]){
if(from[x.second] == i){
dist[x.second] = max(dist[x.second], x.first + 1);
}else{
from[x.second] = i;
dist[x.second] = x.first + 1;
curr.push_back(x.second);
}
}
}
t[i].push_back({0, i});
for(int x : curr){
t[i].push_back({dist[x], x});
}
sort(t[i].begin(), t[i].end(), greater <pii>());
if((int)t[i].size() > B){
t[i].erase(t[i].begin() + B, t[i].end());
}
}
while(q--){
int node, nr;
cin >> node >> nr;
vector <int> bad;
for(int i = 1; i <= nr; i++){
int x;
cin >> x;
bad.push_back(x);
no[x] = true;
}
int ans = -1;
if((int)bad.size() > B){
vector <int> dp(n + 1, -1);
dp[node] = 0;
for(int i = node; i >= 1; i--){
if(dp[i] != -1){
ans = max(ans, dp[i]);
for(int vec : adj[node]){
dp[vec] = max(dp[vec], dp[node] + 1);
}
}
}
}else{
for(pii x : t[node]){
if(!no[x.second]){
ans = x.first;
break;
}
}
}
cout << ans << '\n';
for(int x : bad){
no[x] = false;
}
}
return 0;
}
/*
5 6 3
1 2
2 4
3 4
1 3
3 5
4 5
4 1 1
5 2 2 3
2 3 1 4 5
*/
