#include <bits/stdc++.h>
#define node second
#define dist first
#define all(x) x.begin(), x.end()
using namespace std;
typedef pair<int,int> ii;
const int B = 150;
vector<ii> best[100005];
vector<int> adj[100005];
bool ban[100005];
int memo[100005];
int vis[100005];
int inTemp[100005];
void dfs(int u){
best[u].push_back(ii(0,u));
for(int v : adj[u]){
if(best[v].empty()) dfs(v);
for(ii x : best[v]){
int pos = inTemp[x.node];
if(pos == 0){
inTemp[x.node] = (int) best[u].size();
best[u].push_back(ii(x.dist+1,x.node));
}
else{
best[u][pos].dist = max(best[u][pos].dist,x.dist+1);
}
}
}
for(ii x : best[u]) inTemp[x.node] = 0;
nth_element(best[u].begin(), best[u].begin() + B, best[u].end(), [&](ii a, ii b){ return a.dist > b.dist; });
while(best[u].size() > B) best[u].pop_back();
vis[u] = true;
}
int dfs2(int u){
if(memo[u] != -1) return memo[u];
int ans = 0;
if(ban[u]) ans = -10234567;
for(int v : adj[u]){
ans = max(ans, dfs2(v)+1);
}
memo[u] = ans;
return memo[u];
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
int n, m, Q; cin >> n >> m >> Q;
fill(inTemp, inTemp+n+1, -1);
while(m--){
int u, v; cin >> u >> v;
adj[v].push_back(u);
}
for(int i = 1;i <= n;i++){
if(!vis[i]) dfs(i);
}
while(Q--){
int t; cin >> t;
int S; cin >> S;
vector<int> cannot;
for(int i = 0;i < S;i++){
int x; cin >> x;
cannot.push_back(x);
}
for(int x : cannot) ban[x] = true;
if(S >= B){
fill(memo, memo+n+1, -1);
cout << max(-1, dfs2(t)) << "\n";
}
else{
int ans = -1;
for(ii x : best[t]){
if(!ban[x.node]){
ans = max(ans,x.dist);
}
}
cout << ans << "\n";
}
for(int x : cannot) ban[x] = false;
}
}
