#include <bits/stdc++.h>
#define int long long
#define pi pair<int,int>
#define pb push_back
#define V vector
#define vi V<int>
#define mi map<int,int>
#define MOD 1000000007
#define MOD2 998244353
#define mp make_pair
#define ins insert
#define qi queue<int>
#define pqi priority_queue<int>
#define si set<int>
#define v2i V<vi>
#define v3i V<v2i>
#define v4i V<v3i>
#define v5i V<v4i>
#define INF 1e18
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()
#define fastio ios_base::sync_with_stdio(false); cin.tie(nullptr);
#define endl "\n"
#define lb lower_bound
#define ub upper_bound
#define print(x) cout << x<<" ";
#define vpi V<pi>
#define Y cout<<"YES"<<endl;
#define NO cout<<"NO"<<endl;
#define msi multiset<int>
#define F first
#define S second
#define ld long double
#define RE return;
#define IMP cout<<-1<<endl;return;
using namespace std;
template <typename T>
std::istream& operator>>(std::istream& in, std::vector<T>& vec) {
for (T& x : vec) {
in >> x;
}
return in;
}
const int block = 350;
signed main(){
fastio;
int n,m,q; cin>>n>>m>>q;
v2i adj(n);
for(int i=0; i<m; i++){
int s,e; cin>>s>>e; s--;e--;
adj[e].pb(s);
}
V<set<pi>> mx(n);
for(int i=0; i<n; i++){
mx[i].ins({0,i});
set<pi> used;
for(auto&x: adj[i]){
for(auto &y: mx[x]){
auto it = used.lb({y.S,0});
if(it!=used.end() && (*it).F == y.S){
pi fnd = *it;
if(y.F+1 > fnd.S){
used.erase(it);
used.ins({fnd.F, y.F+1});
swap(fnd.F,fnd.S);
mx[i].erase(mx[i].find(fnd));
mx[i].ins({y.F+1, y.S});
}
}else {
mx[i].ins({y.F+1, y.S});
used.ins({y.S, y.F+1});
if(sz(mx[i])>block){
pi rip = *mx[i].begin();
mx[i].erase(mx[i].begin());
used.erase(used.find({rip.S,rip.F}));
}
}
}
}
}
while(q--){
int t,y; cin >> t>>y;
t--;
si notal; for(int i=0; i<y; i++){int x; cin >> x; notal.ins(x-1);}
if(y>=block){
vi dp(n,-INF);
for(int i=0; i<n; i++)if(!notal.count(i)){
dp[i]=0;
for(auto &x: adj[i]){
dp[i] = max(dp[x]+1, dp[i]);
}
}
cout << (dp[t]<0? -1 : dp[t])<<endl;
}else{
int ans = -1;
for(auto &x: mx[t])if(!notal.count(x.S)) ans = x.F;
cout<<ans<<endl;
}
}
}
