#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int mxN = 1e5+5;
int n, m, q, k, ok[mxN];
vector <pair <int, int>> dp[mxN];
vector <int> adj[mxN], mx(mxN, -1);
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++) {
vector <int> vis;
dp[u].emplace_back(0, u);
for (auto v : adj[u]) for (auto &[val, idx] : dp[v]) {
if (mx[idx] == -1) {
vis.emplace_back(idx);
mx[idx] = val+1;
} else {
mx[idx] = max(mx[idx], val+1);
}
}
for (auto &e : vis) dp[u].emplace_back(mx[e], e);
sort(dp[u].rbegin(), dp[u].rend());
while ((int) dp[u].size() > k) dp[u].pop_back();
for (auto &e : vis) mx[e] = -1;
}
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) {
int ans = -1;
for (auto &[val, idx] : dp[u]) if (!ok[idx]) { ans = val; break; }
cout << ans << '\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;
}
}
