/**
____ ____ ____ ____ ____
||a |||t |||o |||d |||o ||
||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|
**/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N_MAX = 100000;
int N, M, Q;
vector <int> out[N_MAX + 2];
vector <int> in[N_MAX + 2];
int K;
vector <pair <int, int>> dp[N_MAX + 2];
bool aux[N_MAX + 2];
int maxLen[N_MAX + 2];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> N >> M >> Q;
for(int i = 1; i <= M; i++)
{
int u, v;
cin >> u >> v;
out[u].push_back(v);
in[v].push_back(u);
}
K = 100;
for(int u = 1; u <= N; u++)
{
vector <pair <int, int>> vec;
for(int v : in[u])
{
for(pair <int, int> p : dp[v])
vec.push_back(p);
}
sort(vec.begin(), vec.end(), greater <pair <int, int>> ());
for(pair <int, int> p : vec)
if(aux[p.second] == false)
{
aux[p.second] = true;
dp[u].push_back(make_pair(p.first + 1, p.second));
if((int) dp[u].size() == K)
break;
}
if((int) dp[u].size() < K)
dp[u].push_back(make_pair(0, u));
for(pair <int, int> p : dp[u])
aux[p.second] = false;
}
for(int i = 1; i <= Q; i++)
{
int u;
cin >> u;
int cnt;
cin >> cnt;
vector <int> exclude (cnt);
for(int j = 0; j < cnt; j++)
cin >> exclude[j];
for(int v : exclude)
aux[v] = true;
if(cnt < K)
{
int pos = 0;
while(pos < (int) dp[u].size() && aux[dp[u][pos].second] == true)
pos++;
if(pos == (int) dp[u].size())
cout << "-1\n";
else
cout << dp[u][pos].first << "\n";
}
else
{
for(int v = 1; v <= N; v++)
{
maxLen[v] = (aux[v] == false ? 0 : INT_MIN);
for(int w : in[v])
maxLen[v] = max(maxLen[v], maxLen[w] + 1);
}
if(maxLen[u] < 0)
cout << "-1\n";
else
cout << maxLen[u] << "\n";
}
for(int v : exclude)
aux[v] = false;
}
return 0;
}
