#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 10;
const int INF = 1e9;
const int B = 3000;
int n, m, q;
vector<int> g0[N], g1[N];
int solve(int t, vector<int> st) {
vector<int> dp(n + 1, -2 * INF);
dp[t] = 0;
for(int i = n; i >= 1; i--) {
for(int to : g0[i])
dp[i] = max(dp[i], dp[to] + 1);
}
bool us[n + 1] = {};
for(int c : st)
us[c] = 1;
int res = -INF;
for(int i = 1; i <= n; i++) {
if(us[i]) continue;
res = max(res, dp[i]);
}
if(res == -INF) res = -1;
return res;
}
vector<pair<int, int>> v[N];
bool us[N];
void merge(int i, int j) {
vector<pair<int, int>> res;
int lb = 0, rb = 0;
// for(auto [d, c] : v[i]) cout << c << ' ';
// cout << '\n';
// for(auto [d, c] : v[j]) cout << c << ' ';
// cout << '\n';
// for(auto [d, c] : res) cout << c << ' ';
// cout << '\n';
while((int)res.size() < B && (lb < (int)v[i].size() || rb < (int)v[j].size())) {
while(lb < (int)v[i].size() && us[v[i][lb].second]) lb++;
while(rb < (int)v[j].size() && us[v[j][rb].second]) rb++;
int w1 = (lb < (int)v[i].size() ? v[i][lb].first : -INF);
int w2 = (rb < (int)v[j].size() ? v[j][rb].first : -INF);
if(w1 > w2) res.push_back({v[i][lb].first, v[i][lb].second}), lb++;
else res.push_back({v[j][rb].first, v[j][rb].second}), rb++;
us[res.back().second] = 1;
}
v[i] = res;
for(auto [d, c] : v[i]) us[c] = 0;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
cin >> n >> m >> q;
for(int i = 1; i <= m; i++) {
int u, v;
cin >> u >> v;
g0[u].push_back(v);
g1[v].push_back(u);
}
for(int i = 1; i <= n; i++) {
for(int from : g1[i]) {
merge(i, from);
}
for(auto &x : v[i]) x.first++;
v[i].push_back({0, i});
}
while(q--) {
int t, k;
cin >> t >> k;
vector<int> y(k);
for(int i = 0; i < k; i++) {
cin >> y[i];
us[y[i]] = 1;
}
int ans = 0;
if(k >= B) ans = solve(t, y);
else {
int lb = 0;
while(lb < (int)v[t].size() && us[v[t][lb].second])
lb++;
if(lb == (int)v[t].size()) ans = -1;
else ans = v[t][lb].first;
}
cout << ans << '\n';
for(int c : y) us[c] = 0;
}
}
