#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 5, inf = 2e9;
int n, m, Q;
vector <int> g[N], adj[N];
int topo[N], deg[N], dp[N], c[N], f[303][N];
bool busy[N];
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
// freopen(".INP", "r", stdin);
// freopen(".OUT", "w", stdout);
cin >> n >> m >> Q;
while (m--) {
int u, v;
cin >> u >> v;
g[u].push_back(v);
adj[v].push_back(u);
deg[v]++;
}
queue <int> q;
for (int i=1;i<=n;++i) if (deg[i] == 0) q.push(i);
int idd = 0;
while (!q.empty()) {
int u = q.front();
topo[++idd] = u;
q.pop();
for (int v : g[u]) if (--deg[v] == 0) q.push(v);
}
int sq = 200, mq = min(n, 300);
for (int i=1;i<=mq;++i) {
int u = topo[i];
fill(f[i], f[i]+n+1, -inf);
f[i][u] = 0;
for (int j=1;j<=n;++j) {
int v = topo[j];
for (int x : g[v]) f[i][x] = max(f[i][x], f[i][v] + 1);
}
}
while (Q--) {
int t, y, ans = -1;
cin >> t >> y;
for (int i=1;i<=y;++i) cin >> c[i], busy[c[i]] = 1;
if (y >= sq) {
fill(dp, dp+n+1, -inf);
dp[t] = 0;
for (int i=n;i>=1;--i) {
int u = topo[i];
for (int v : adj[u]) dp[v] = max(dp[u] + 1, dp[v]);
}
for (int i=1;i<=n;++i) if (!busy[i]) ans = max(ans, dp[i]);
}
else {
for (int i=1;i<=mq;++i)
if (!busy[topo[i]]) ans = max(ans, f[i][t]);
}
for (int i=1;i<=y;++i) busy[c[i]] = 0;
cout << ans << '\n';
}
}
