#include <bits/stdc++.h>
using namespace std;
#define N 100'001
int dp[N], mark[N]{};
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, m, q;
cin >> n >> m >> q;
vector<pair<int, int>> e(m);
vector<vector<int>> adj(n + 1);
for (auto &[u, v] : e) cin >> v >> u, adj[u].push_back(v);
sort(e.rbegin(), e.rend());
const int B = 150;
vector<vector<pair<int, int>>> p(n + 1);
for (int i = 1; i <= n; i++) {
p[i].emplace_back(i, 0);
for (int v : adj[i]) {
for (auto [id, d] : p[v]) {
p[i].emplace_back(id, d + 1);
}
}
sort(p[i].begin(), p[i].end());
int l = 0;
for (int r = 1; r < p[i].size(); r++) {
if (p[i][r].first == p[i][l].first) {
p[i][l] = p[i][r];
}
else {
p[i][++l] = p[i][r];
}
}
l++;
while (p[i].size() > l) p[i].pop_back();
l = min(l, B);
sort(p[i].begin(), p[i].end(), [&](auto i, auto j) {
return i.second > j.second;
});
while (p[i].size() > l) p[i].pop_back();
}
int timer = 0;
while (q--) {
timer++;
int t;
cin >> t;
int k;
cin >> k;
vector<int> c(k);
for (int &i : c) cin >> i;
while (k > 0 && c[k - 1] > t) {
c.pop_back();
k--;
}
for (int i : c) mark[i] = timer;
if (k >= B) {
memset(dp, -1, sizeof dp);
dp[t] = 0;
for (auto [u, v] : e) {
if (dp[u] >= 0) {
dp[v] = max(dp[v], dp[u] + 1);
}
}
int ans = -1, j = 0;
for (int i = 1; i <= n; i++) {
if (j < k && c[j] == i) j++;
else if (dp[i] >= 0) {
ans = max(ans, dp[i]);
}
}
cout << ans << '\n';
}
else {
int ans = -1;
for (auto [id, d] : p[t]) {
if (mark[id] != timer) {
ans = d;
break;
}
}
cout << ans << '\n';
}
}
return 0;
}
