#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> in;
arr<deq<pii>, N> dp;
void prcmp() {
for (int u = 1; u <= n; u++) {
vec<deq<pii>> trns;
for (int v : in[u]) trns.push_back(dp[v]);
hset<int> usd;
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';
// }
}
arr<int, N> dst;
arr<bool, N> vs;
queue<int> ord;
void bfs(int st) {
dst.fill(INF), vs.fill(false);
dst[st] = 0, ord.push(st);
while (ord.size()) {
int u = ord.back(); ord.pop();
if (vs[u]) continue;
vs[u] = true;
for (int v : in[u]) {
int nw_dst = dst[u] + 1;
if (nw_dst >= dst[v]) continue;
dst[v] = nw_dst, ord.push(v);
}
}
}
hset<int> dlt;
void cmp() {
dlt.clear();
int u, x; cin >> u >> x;
for (int i = 1; i <= x; i++) { int v; cin >> v; dlt.insert(v); }
if (x <= k) {
int mx = -1;
for (pii y : dp[u])
if (!dlt.count(y.sec))
mx = max(mx, y.fir);
cout << mx << '\n';
} else {
bfs(u);
int mx = -1;
for (int v = 1; v <= n; v++)
if (!dlt.count(v) && vs[v]) mx = max(mx, dst[v]);
cout << mx << '\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;
in[v].push_back(u);
}
prcmp();
for (int i = 1; i <= q; i++) cmp();
}
