#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int mxN = 1e5+5;
int n, m, q, k, ok[mxN];
set <pair <int, int>> dp[mxN], dp2[mxN];
vector <int> adj[mxN];
int main() {
ios::sync_with_stdio(0), cin.tie(0);
cin >> n >> m >> q; k = 100;
for (int i = 0, u, v; i < m; i++) cin >> u >> v, adj[max(u, v)].emplace_back(min(u, v));
for (int u = 1; u <= n; u++) {
dp[u].emplace(0, u);
dp2[u].emplace(u, 0);
for (auto v : adj[u]) for (auto &e : dp[v]) {
if ((int) dp[u].size() == k && -(*prev(dp[u].end())).first >= -e.first+1) break;
auto it = dp2[u].upper_bound(make_pair(e.second, INT_MIN));
if (it != dp2[u].end() && (*it).first == e.second) {
if ((*it).second > e.first - 1) {
dp[u].erase(dp[u].find(make_pair((*it).second, (*it).first)));
} else continue;
}
dp[u].emplace(e.first-1, e.second);
dp2[u].emplace(e.second, e.first-1);
if ((int) dp[u].size() > k) {
dp2[u].erase(dp2[u].find(make_pair((*prev(dp[u].end())).second, (*prev(dp[u].end())).first)));
dp[u].erase(prev(dp[u].end()));
}
}
}
while (q--) {
int u, y; cin >> u >> y;
vector <int> X;
for (int i = 0, e; i < y; i++) { cin >> e; if (e <= u) X.emplace_back(e), ok[e] = 1; }
y = X.size();
if (y < k) {
auto it = dp[u].begin();
while (it != dp[u].end() && ok[(*it).second]) it++;
if (it == dp[u].end()) cout << -1 << '\n';
else cout << -(*it).first << '\n';
} else {
vector <int> DP(n+1, INT_MIN);
for (int i = 1; i <= u; i++) { if (!ok[i]) DP[i] = 0; for (auto v : adj[i]) DP[i] = max(DP[i], DP[v]+1); }
cout << max(-1, DP[u]) << '\n';
}
for (auto &e : X) ok[e] = 0;
}
}
