/*
author: Maksim1744
created: 26.03.2021 23:25:44
*/
#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define sum(a) ( accumulate ((a).begin(), (a).end(), 0ll))
#define mine(a) (*min_element((a).begin(), (a).end()))
#define maxe(a) (*max_element((a).begin(), (a).end()))
#define mini(a) ( min_element((a).begin(), (a).end()) - (a).begin())
#define maxi(a) ( max_element((a).begin(), (a).end()) - (a).begin())
#define lowb(a, x) ( lower_bound((a).begin(), (a).end(), (x)) - (a).begin())
#define uppb(a, x) ( upper_bound((a).begin(), (a).end(), (x)) - (a).begin())
template<typename T> vector<T>& operator-- (vector<T>& v){for (auto& i : v) --i; return v;}
template<typename T> vector<T>& operator++ (vector<T>& v){for (auto& i : v) ++i; return v;}
template<typename T> istream& operator>>(istream& is, vector<T>& v){for (auto& i : v) is >> i; return is;}
template<typename T> ostream& operator<<(ostream& os, vector<T>& v){for (auto& i : v) os << i << ' '; return os;}
template<typename T, typename U> pair<T,U>& operator-- (pair<T, U> &p){--p.first; --p.second; return p;}
template<typename T, typename U> pair<T,U>& operator++ (pair<T, U> &p){++p.first; ++p.second; return p;}
template<typename T, typename U> istream& operator>>(istream& is, pair<T, U>& p){is >> p.first >> p.second; return is;}
template<typename T, typename U> ostream& operator<<(ostream& os, pair<T, U>& p){os << p.first << ' ' << p.second; return os;}
template<typename T, typename U> pair<T,U> operator-(pair<T,U> a, pair<T,U> b){return mp(a.first-b.first, a.second-b.second);}
template<typename T, typename U> pair<T,U> operator+(pair<T,U> a, pair<T,U> b){return mp(a.first+b.first, a.second+b.second);}
template<typename T, typename U> void umin(T& a, U b){if (a > b) a = b;}
template<typename T, typename U> void umax(T& a, U b){if (a < b) a = b;}
#ifdef HOME
#define SHOW_COLORS
#include "C:/C++ libs/print.cpp"
#else
#define show(...) 42
#define mclock 42
#define shows 42
#define debug if (false)
#endif
int main() {
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
int n, m, q;
cin >> n >> m >> q;
const int B = 450;
vector<vector<int>> g(n), gi(n);
for (int i = 0; i < m; ++i) {
int a, b;
cin >> a >> b;
--a; --b;
g[a].pb(b);
gi[b].pb(a);
}
vector<int> ui(n, -1);
int ustep = 0;
auto mrg = [&](vector<pair<int, int>> &a, vector<pair<int, int>> b) {
++ustep;
int ia = 0, ib = 0;
for (int i = 0; i < b.size(); ++i) {
b[i].first++;
}
vector<pair<int, int>> res;
while ((ia < a.size() || ib < b.size()) && res.size() < B) {
bool cha;
if (ia == a.size()) cha = false;
else if (ib == b.size()) cha = true;
else if (a[ia].first > b[ib].first) cha = true;
else cha = false;
if (cha) {
if (ui[a[ia].second] != ustep)
res.pb(a[ia]);
ui[a[ia].second] = ustep;
++ia;
} else {
if (ui[b[ib].second] != ustep)
res.pb(b[ib]);
ui[b[ib].second] = ustep;
++ib;
}
}
show(a, b, res);
return res;
};
vector<bool> u(n, false);
vector<vector<pair<int, int>>> dp(n);
vector<int> order;
function<void(int)> dfs1 = [&](int v) {
u[v] = true;
dp[v].eb(0, v);
for (int k : gi[v]) {
if (!u[k]) {
dfs1(k);
}
dp[v] = mrg(dp[v], dp[k]);
}
order.pb(v);
};
for (int i = 0; i < n; ++i) {
if (!u[i])
dfs1(i);
}
show(gi);
show(dp);
vector<int> dist(n);
show(g);
reverse(order.begin(), order.end());
while (q--) {
int v, y;
cin >> v >> y;
--v;
++ustep;
for (int i = 0; i < y; ++i) {
int k;
cin >> k;
--k;
ui[k] = ustep;
}
if (y < B) {
int ans = -1;
for (auto [a, b] : dp[v]) {
if (ui[b] != ustep) {
ans = a;
break;
}
}
cout << ans << '\n';
} else {
int ans = -1;
dist.assign(n, -1e9);
show(order);
show(v);
dist[v] = 0;
for (int k : order) {
for (int u : g[k])
dist[k] = max(dist[k], dist[u] + 1);
if (ui[k] != ustep)
ans = max(ans, dist[k]);
}
show(dist);
cout << ans << '\n';
}
}
return 0;
}
