#include <bits/stdc++.h>
#define X first
#define Y second
#define MP make_pair
#define ll long long
using namespace std;
const int N = 1e5 + 1, BS = 300;
const ll INF = 1e18;
int n, m, q, dsu[N], used[N], cnt[N], dp[N];
vector< int > g[N];
vector< pair<int, int> > gg[N];
void prep(){
cin >> n >> m >> q;
for(int i = 1, x, y;i <= m;i++){
cin >> x >> y;
g[y].push_back(x);
}
set< pair<int, int> > act;
for(int i = 1;i <= n;i++){
gg[i].push_back(MP(0, i));
for(int from: g[i]){
for(pair<int, int> tmp: gg[from]){
if(used[tmp.Y] != i)
dp[tmp.Y] = 0, used[tmp.Y] = i;
if(tmp.X + 1 > dp[tmp.Y]){
act.erase(MP(dp[tmp.Y], tmp.Y));
dp[tmp.Y] = tmp.X + 1;
act.insert(MP(dp[tmp.Y], tmp.Y));
if(act.size() > BS)
used[act.begin()->Y] = -1, act.erase(act.begin());
}
}
}
while(!act.empty()){
gg[i].push_back(*act.begin());
act.erase(act.begin());
}
act.clear();
}
}
int main () {
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
prep();
for(int pos, len, x, T = N + 1;q--;T++){
cin >> pos >> len;
for(int j = 1;j <= len;j++){
cin >> x, used[x] = T;
}
if(len > BS){
for(int i = 1;i <= pos;i++){
dp[i] = 0, cnt[i] = 0;
if(used[i] != T)
cnt[i] = 1;
for(int from: g[i]){
if(dp[from] + 1 > dp[i] && cnt[from])
dp[i] = dp[from] + 1, cnt[i] = cnt[from];
else if(dp[from] + 1 == dp[i] && cnt[from])
cnt[i]++;
}
}
}
else {
dp[pos] = 0, cnt[pos] = 0;
for(pair<int, int> tmp: gg[pos]){
if(used[tmp.Y] == T)
continue;
if(tmp.X > dp[pos])
dp[pos] = tmp.X, cnt[pos] = 1;
else if(tmp.X == dp[pos])
cnt[pos]++;
}
}
cout << (cnt[pos] == 0 ? -1: dp[pos]) << "\n";
}
}
