#define local
#ifndef local
#include ""
#endif
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
#define int long long
#define fi first
#define se second
#define pb push_back
#define mp make_pair
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;
const int N = 3e5 + 5;
const int oo = 1e18 + 7, mod = 1e9 + 7;
mt19937 rng(1);
int rnd(int l, int r){
int temp = rng() % (r - l + 1);
return abs(temp) + l;
}
int n, m, q;
const int S = 105;
ii mx[N][S];
int itr[N];
bool ck[N], ck2[N], vis[N];
vector<int> lst[N], nxt[N];
int len[N];
#ifdef local
void process(){
cin >> n >> m >> q;
for(int i = 1; i <= m; i++){
int x, y;
cin >> x >> y;
lst[y].pb(x);
nxt[x].pb(y);
}
for(int i = 1; i <= n; i++){
vector<ii> vc;
for(auto it : lst[i]){
//cout << "EDGE " << i << " " << it << "\n";
//cout << mx[i][j].se << "\n";
for(int j = 1; j <= 100; j++) vc.pb({mx[it][j].fi + 1, mx[it][j].se});
//vc.pb({1, it});
}
//for(auto it : vc) cout << "OK " << it.fi << " " << it.se << "\n";
sort(vc.begin(), vc.end(), greater<ii>());
int itr = 0;
for(auto it : vc){
//cout << it.se << "\n";
if(vis[it.se]) continue;
// cout << "OKAY " << it.fi << " " << it.se << "\n";
itr++;
if(itr > 100) break;
vis[it.se] = 1;
mx[i][itr] = it;
}
// cout << i << " " << itr << "\n";
if(itr < 100){
itr++;
mx[i][itr] = {0, i};
}
for(int j = 1; j <= 100; j++) vis[mx[i][j].se] = 0;
// cout << i << " ";
// for(int j = 1; j <= itr; j++) cout << mx[i][j].fi << " " << mx[i][j].se << " ";
// cout << "\n";
//priority_queue<ii, vector<ii>, greater<ii>> pq;
}
while(q--){
int s, x;
cin >> s >> x;
vector<int> vc;
for(int i = 1; i <= x; i++){
int y;
cin >> y;
vc.pb(y);
ck2[y] = 1;
}
int answer = -1;
for(int i = 1; i <= 100; i++){
if(mx[s][i].se == 0) continue;
if(!ck2[mx[s][i].se]){
answer = mx[s][i].fi;
break;
}
}
if(answer < 0){
for(int i = 1; i <= n; i++) len[i] = -oo;
len[s] = 0;
for(int i = s - 1; i >= 1; i--){
for(auto it : nxt[i]) len[i] = max(len[i], len[it] + 1);
}
for(int i = 1; i <= s; i++) if(!ck2[i]) answer = max(answer, len[i]);
}
for(auto it : vc) ck2[it] = 0;
cout << answer << "\n";
}
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
process();
}
#endif
