// #pragma GCC optimize("Ofast")
// #pragma GCC target("popcnt")
#include <bits/stdc++.h>
using namespace std;
// #define int long long
// #define double long double
#define mkp make_pair
#define txt freopen("shortcut.in", "r", stdin), freopen("shortcut.out", "w", stdout);
const int N = 2e5 + 100, K = 150, inf = 0, mod = 1e9 + 7;
const double eps = 1e-6;
vector<int> gr[N];
set<pair<int, int>> S[N];
set<pair<int, int>> R[N];
int D[N];
void solve()
{
int n, m, Q;
cin >> n >> m >> Q;
for(int i = m, a, b; i--;)
{
cin >> a >> b;
gr[a].push_back(b);
}
for(int i = 1; i <= n; i++)
{
S[i].insert({0, i});
R[i].insert({i, 0});
}
for(int i = 1; i <= n; i++)
{
for(auto x : gr[i])
{
for(auto j : R[i])
{
auto it = R[x].lower_bound({j.first, 0});
if(it != R[x].end() && it->first == j.first)
{
pair<int, int> p = *it;
R[x].erase(it);
S[x].erase({p.second, p.first});
p = max(p, {j.first, j.second + 1});
R[x].insert(p);
S[x].insert({p.second, p.first});
}
else
{
R[x].insert({j.first, j.second + 1});
S[x].insert({j.second + 1, j.first});
}
}
while(S[x].size() > K)
{
R[x].erase({S[x].begin()->second, S[x].begin()->first});
S[x].erase(S[x].begin());
}
}
}
for(int qq = Q, x, y; qq--;)
{
cin >> x >> y;
vector<int> vec(y);
for(auto &i : vec)
{
cin >> i;
D[i] = -1e9;
}
if(y < K)
{
int mx = -1;
for(auto i : S[x])
{
if(D[i.second] >= 0)
mx = i.first;
}
cout << mx << "\n";
}
else
{
for(int i = 1; i <= n; i++)
{
for(auto j : gr[i])
D[j] = max(D[j], D[i] + 1);
}
cout << max(-1, D[x]) << '\n';
for(int i = 1; i <= n; i++)
D[i] = 0;
}
for(auto i : vec)
D[i] = 0;
}
}
signed main()
{
// txt;
ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
int T = 1;
for(; T--; solve());
}
/*
*/
