#pragma GCC optimize("O3", "unroll-loops")
#pragma GCC target("avx2")
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define arr array
#define vec vector
#define deq deque
#define pii pair<int, int>
#define fir first
#define sec second
#define hset unordered_set
const int N = 1e5 + 5, INF = 1e12;
int n, m, q, k;
arr<vec<int>, N> out, in;
arr<deq<pii>, N> dp;
vec<deq<pii>> trns;
hset<int> usd;
void prcmp() {
for (int u = 1; u <= n; u++) {
trns.clear();
for (int v : in[u]) trns.push_back(dp[v]);
usd.clear();
for (int i = 1; i <= k; i++) {
pii bst = {-1, u};
for (int j = 0; j < trns.size(); j++) {
while (trns[j].size() && usd.count(trns[j].front().sec))
trns[j].pop_front();
if (trns[j].size()) bst = max(bst, trns[j].front());
}
usd.insert(bst.sec);
dp[u].push_back({bst.fir + 1, bst.sec});
}
}
// for (int u = 1; u <= n; u++) {
// cout << u << ": ";
// for (pii x : dp[u]) cout << x.fir << " " << x.sec << " ";
// cout << '\n';
// }
}
hset<int> dlt;
arr<int, N> pd;
void cmp() {
dlt.clear();
int u, x; cin >> u >> x;
for (int i = 1; i <= x; i++) { int v; cin >> v; dlt.insert(v); }
auto fst = [&]() {
int mx = -1;
for (pii y : dp[u])
if (!dlt.count(y.sec))
mx = max(mx, y.fir);
return mx;
};
auto slw = [&]() {
pd.fill(-INF);
pd[u] = 0;
for (int v = u - 1; v >= 1; v--)
for (int w : out[v])
pd[v] = max(pd[v], pd[w] + 1);
int mx = -1;
for (int v = 1; v <= n; v++)
if (!dlt.count(v) && pd[v] >= 0) mx = max(mx, pd[v]);
return mx;
};
if (x <= k) {
// cout << u << ": " << fst() << " " << slw() << endl;
// assert(fst() == slw());
cout << fst() << '\n';
} else {
cout << slw() << '\n';
}
}
signed main() {
// freopen("in", "r", stdin);
cin.sync_with_stdio(false), cin.tie(0);
cin >> n >> m >> q; k = max((int) sqrtl(n), 1ll);
for (int i = 1; i <= m; i++) {
int u, v; cin >> u >> v;
out[u].push_back(v), in[v].push_back(u);
}
prcmp();
for (int i = 1; i <= q; i++) cmp();
}
