#include <bits/stdc++.h>
using namespace std;
const int B = 300;
int dp[100010][B+1];
int st[100010][B+1];
vector<int> adj[100010];
int idx[100010];
int chk[100010];
int dp2[100010];
int main() {
int n, m, q;
cin >> n >> m >> q;
for (int i=0; i<m; i++) {
int u, v;
cin >> u >> v;
adj[v].push_back(u);
}
memset(dp, -1, sizeof(dp));
for (int i=1; i<=n; i++) {
for (auto &j : adj[i]) {
idx[j] = 0;
}
for (int j=0; j<B; j++) {
int mx = -1, pv = -1;
for (auto &k : adj[i]) {
if (mx < dp[k][idx[k]]) {
mx = dp[k][idx[k]];
pv = k;
}
}
if (pv == -1) break;
dp[i][j] = mx + 1;
st[i][j] = st[pv][idx[pv]];
idx[pv] ++;
}
for (int j=0; j<B; j++) {
if (dp[i][j] == -1) {
dp[i][j] = 0;
st[i][j] = i;
break;
}
}
}
while (q --) {
int x;
cin >> x;
int k;
cin >> k;
vector<int> num(k);
for (int i=0; i<k; i++) {
cin >> num[i];
chk[num[i]] = 1;
}
if (k < B) {
for (int i=0; i<B; i++) {
if (!chk[st[x][i]]) {
cout << dp[x][i] << '\n';
break;
}
}
}
else {
memset(dp2, -1, sizeof(dp2));
for (int i=1; i<=x; i++) {
if (!chk[i]) dp2[i] = 0;
for (auto &j : adj[i]) {
if (dp2[j] != -1)
dp2[i] = max(dp2[i], dp2[j] + 1);
}
}
cout << dp2[x] << '\n';
}
for (int i=0; i<k; i++) {
chk[num[i]] = 0;
}
}
}
