#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
using u64 = unsigned long long;
using ld = long double;
using ii = pair<int, int>;
const int N = 1e5 + 100;
const int B = 300;
const int INF = 1e9;
vector<int> g[N];
vector<ii> dp[N];
ii tmp[B];
int id[N], tms = 1, n, m, q;
void merge(vector<ii>& dest, vector<ii>& src) {
int i = 0, j = 0, k = 0;
int n = size(dest), m = size(src);
while(i < n && j < m && k < B) {
auto [du, u] = dest[i];
auto& [dv, v] = src[j];
++dv;
if(id[u] == tms) {
++i, --dv;
continue;
} else if(id[v] == tms) {
++j, --dv;
continue;
} else if(du > dv) {
id[u] = tms;
tmp[k++] = dest[i++];
} else {
id[v] = tms;
tmp[k++] = src[j++];
}
--dv;
}
while(i < n && k < B) {
auto [du, u] = dest[i++];
if(id[u] == tms) continue;
tmp[k++] = dest[i - 1];
}
while(j < m && k < B) {
auto& [dv, v] = src[j++];
++dv;
if(id[v] != tms) tmp[k++] = src[j - 1];
--dv;
}
dest.resize(k);
for(int i = 0; i < k; ++i) dest[i] = tmp[i];
++tms;
}
void solve() {
cin >> n >> m >> q;
for(int i = 0; i < m; ++i) {
int u, v;
cin >> u >> v;
--u, --v;
g[u].push_back(v);
}
for(int i = 0; i < n; ++i) dp[i].emplace_back(0, i);
for(int u = 0; u < n; ++u)
for(int v : g[u])
merge(dp[v], dp[u]);
vector<int> dist(n);
for(int i = 0; i < q; ++i) {
int s, y, ans = -1;
cin >> s >> y;
--s;
if(y >= B) {
fill(dist.begin(), dist.end(), 0);
for(int j = 0; j < y; ++j) {
int u;
cin >> u;
dist[u - 1] = -INF;
}
for(int u = 0; u <= s; ++u)
for(int v : g[u])
dist[v] = max(dist[v], dist[u] + 1);
cout << max(-1, dist[s]) << '\n';
} else {
for(int j = 0; j < y; ++j) {
int u;
cin >> u;
id[u - 1] = tms;
}
for(auto [d, u] : dp[s]) {
if(id[u] == tms) continue;
ans = max(ans, d);
}
cout << ans << '\n';
++tms;
}
}
}
int main() {
ios_base :: sync_with_stdio(false);
cin.tie(0);
int t = 1;
//cin >> t;
while(t--) solve();
return 0;
}
