#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> ii;
typedef vector<int> vi;
struct query{
int id;
unordered_set<int> cannot;
};
static set<ii, greater<ii> > dp[100005];
static int offset[100005]; ///dp[i] + offset[i] = actual value
static vi adj[100005];
static int answer[100005];
static vector<query> queries[100005];
int main(){
//freopen("i.txt","r",stdin);
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, m, q;
cin >> n >> m >> q;
for(int i = 0;i < m;i++){
int a, b;
cin >> a >> b;
a--;
b--;
adj[b].push_back(a);
}
for(int qq = 0;qq < q;qq++){
int y, t;
cin >> y >> t;
y--;
query nQ;
nQ.id = qq;
for(int i = 0;i < t;i++){
int x;
cin >> x;
x--;
nQ.cannot.insert(x);
}
queries[y].push_back(nQ);
}
for(int u = 0;u < n;u++){
dp[u].insert(ii(0,u));
for(int v : adj[u]){
if(dp[u].size() >= dp[v].size()){
for(ii x : dp[v]){
dp[u].insert(ii(x.first+1+offset[v]-offset[u],x.second));
}
}
else{
swap(dp[u],dp[v]);
swap(offset[u],offset[v]);
offset[u]++;
offset[v]--;
for(ii x : dp[v]){
dp[u].insert(ii(x.first+1+offset[v]-offset[u],x.second));
}
}
}
for(query qq : queries[u]){
bool can = false;
for(ii x : dp[u]){
if(qq.cannot.find(x.second) == qq.cannot.end()){
answer[qq.id] = x.first + offset[u];
can = true;
break;
}
}
if(!can) answer[qq.id] = -1;
}
/*
for(ii x : dp[u]){
cout << "(" << x.first + offset[u] << ", " << x.second << ") ";
}
cout << offset[u] << "\n";
//*/
}
for(int i = 0;i < q;i++){
cout << answer[i] << "\n";
}
}
