// 23 - 12 - 23
#include<bits/stdc++.h>
using namespace std;
#define read() ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define day() time_t now = time(0);char* x = ctime(&now);cerr<<"Right Now Is : "<<x<<"\n"
#define ii pair<int,int>
#define X first
#define Y second
const long long MAX = (int)1e5 + 5;
const long long INF = (int)1e9;
const long long MOD = (int)1e9 + 7;
const int BASE = 100;
int n,m,q;
vector<int> adj[MAX];
int dd[MAX][2];
vector<ii> lenx[MAX];
int mp[MAX];
int dist[MAX];
void solve(int s,int times){
for(int i = 1;i <= s;i++){
dist[i] = 0;
for(auto v : adj[i]){
dist[i] = max(dist[v] + 1,dist[i]);
}
if(dist[i] == 0 && mp[i] == times)dist[i] = -1;
}
cout << dist[s] << '\n';
}
signed main(){
read();
cin >> n >> m >> q;
for(int i = 1,u,v;i <= m;i++){
cin >> u >> v;
adj[v].push_back(u);
}
for(int i = 1;i <= n;i++){
dd[i][0] = 0;
dd[i][1] = i;
vector<int> cur;
cur.push_back(i);
for(auto v : adj[i]){
for(auto e : lenx[v]){
int p = e.Y;
if(dd[p][1] != i){
dd[p][1] = i;
dd[p][0] = -e.X + 1;
cur.push_back(p);
}else{
dd[p][0] = max(dd[p][0],-e.X + 1);
}
}
}
for(auto v : cur)lenx[i].push_back({-dd[v][0],v});
sort(lenx[i].begin(),lenx[i].end());
while(lenx[i].size() > BASE)lenx[i].pop_back();
// cout << i << " :\n";
// for(auto v : lenx[i])cout << -v.X << " " << v.Y << '\n';
}
for(int i = 1;i <= q;i++){
int t,y;
cin >> t >> y;
for(int j = 1,u;j <= y;j++){
cin >> u;
mp[u] = i;
}
if(y >= BASE)solve(t,i);
else {
for(auto v : lenx[t]){
if(mp[v.Y] != i){
cout << -v.X << "\n";
break;
}
}
}
}
}
