#include <bits/stdc++.h>
using namespace std;
#define maxn 100005
int n,m,q;
vector<int> adj[maxn];
vector<pair<int,int>> path[maxn];
int S = 130;
bool used[maxn];
void init(){
cin >> n >> m >> q;
for (int i=0;i<m;i++){
int u,v; cin >> u >> v;
adj[u].push_back(v);
}
for (int i=1;i<=n;i++) path[i].push_back({0,i});
for (int i=1;i<=n;i++){
for (int j:adj[i]){
for (auto [dist,k]: path[i]){
path[j].push_back({dist+1,k});
}
sort(path[j].begin(),path[j].end(),greater<pair<int,int>>());
vector<pair<int,int>> v;
for (int k=0;k<path[j].size();k++){
if (used[path[j][k].second]) continue;
v.push_back(path[j][k]);
used[path[j][k].second] = true;
if (v.size()==S) break;
}
for (auto k:v){
used[k.second] = false;
}
path[j] = v;
}
}
}
bool busy[maxn];
int cnt = 0;
int getDist(int u){
vector<int> dp(n+1,-1);
for (int i=1;i<=n;i++){
if (!busy[i]) dp[i] = max(dp[i],0);
for (int j:adj[i]){
dp[j] = max(dp[j],dp[i]+1);
}
}
return dp[u];
}
void process(){
while (q--){
int u,cntBusy; cin >> u >> cntBusy;
vector<int> busyNode(cntBusy);
for (int i=0;i<cntBusy;i++){
cin >> busyNode[i];
busy[busyNode[i]] = true;
}
if (cntBusy >= S){
cout << getDist(u) << '\n';
}
else {
int ans = -1;
for (auto [dist,v]:path[u]){
if (!busy[v]){
ans = dist;
break;
}
}
cout << ans << '\n';
}
for (int i:busyNode) busy[i] = false;
}
}
int main(){
ios::sync_with_stdio(NULL);
cin.tie(NULL); cout.tie(NULL);
init();
process();
return 0;
}
