#pragma GCC optimize("Ofast")
#pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
/*⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣤⠀⠀⠀⠀⠀⠀⠀⡄⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣤⣿⠛⣿⠀⠀⠀⠀⣤⣿⢻⡇⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣤⣿⡛⠀⣤⣿⣿⣤⣤⣿⣿⣤⢸⡇⠀
⠀⠀⠀⠀⠀⠀⠀⠀⣴⣾⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡇⠀
⠀⠀⠀⠀⠀⠀⠀⣶⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡗⠀
⢠⣼⣿⣿⣿⣿⣤⣾⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷
⢸⣿⣿⡟⠛⠛⢿⣿⣿⣿⣿⣿⣿⣿⣤⣤⣤⣿⣿⣿⣿⣤⣤⣼⣿⣿
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠘⠛⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡟⠋
*/
#define fi first
#define se second
#define pb push_back
#define ins insert
#define sz(a) (int)(a.size())
#define all(x) (x).begin(),(x).end()
#define rep(i, a, b) for(int i = a; i < (b); ++i)
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
#include "debug.h"
#else
#define debug(...)
#endif
//const int mod = 1e9+7;
//const int mod = 998244353;
const int MAXN=1e5+5,R = 100;
const ll inf=1e9,INF=1e18;
int n,m,q;
vi g[MAXN]; vector<pii> cont[MAXN];
bool vis[MAXN] = {0},mark[MAXN] = {0};
int dist[MAXN];
void dfs(int v) {
vis[v] = 1; cont[v].pb({0,v});
vi indices;
for(int i : g[v]) {
if(!vis[i]) dfs(i);
for(auto [d,u] : cont[i]) {
if(dist[u] == -1) indices.pb(u);
dist[u] = max(dist[u],d + 1);
}
}
for(int i : indices) cont[v].pb({dist[i],i});
sort(all(cont[v]),greater<pii>());
while(sz(cont[v]) > R) cont[v].pop_back();
for(int i : indices) dist[i] = -1;
}
int farthest(int v) {
vis[v] = 1;
int ret = (mark[v] ? -inf : 0);
for(int i : g[v]) {
if(!vis[i]) ret = max(ret,1 + farthest(i));
else ret = max(ret,1 + dist[i]);
}
return dist[v] = ret;
}
void solve(int tc = 0){
cin>>n>>m>>q; memset(dist,-1,sizeof(dist));
while(m--) {
int u,v; cin>>u>>v;
g[v].pb(u);
}
rep(i,1,n+1) {
if(!vis[i]) {
dfs(i);
}
}
while(q--) {
int t,y; cin>>t>>y; vi C(y);
for(int &i : C) {
cin>>i;
mark[i] = true;
}
if(y >= R) {
rep(i,1,n+1) vis[i] = 0;
print(max(-1,farthest(t)));
} else {
bool found = 0;
for(auto [d,u] : cont[t]) {
if(!mark[u]) {
found = true;
print(d);
break;
}
}
if(!found) print(-1);
}
for(int i : C) mark[i] = false;
}
}
signed main(){
ios_base::sync_with_stdio(false); cin.tie(0);
int tc=1;
//cin>>tc;
for(int t = 0; t < tc; t++) solve(t);
}
