#include<bits/stdc++.h>
using namespace std;
#define f first
#define s second
#define int long long
const int N = 1e5 + 69;
const int B = 320;
int n, m, q, cnt[N], d[N], vis[N], val[N];
vector<int> in[N];
vector<pair<int, int>> dis[N];
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int tt = 1;
//cin >> tt;
while (tt--) {
cin >> n >> m >> q;
for (int i = 1;i <= m;i++) {
int a, b;
cin >> a >> b;
in[b].push_back(a);
}
for (int i = 1;i <= n;i++) {
vector<int> cur;
cur.push_back(i);
for (auto u : in[i]) {
vis[u] = i;
cur.push_back(u);
val[u] = 1;
for (auto y : dis[u]) {
int x = y.f, d = y.s;
if (vis[x] == i)
val[x] = max(val[x], d + 1);
else {
vis[x] = i;
val[x] = d + 1;
cur.push_back(x);
}
}
}
sort(cur.begin(), cur.end(), [&](int x, int y) {
return val[x] > val[y];
});
for (int j = 0;j < min(B, (int)cur.size());j++)
dis[i].push_back({cur[j], val[cur[j]]});
}
while (q--) {
int s, c;
cin >> s >> c;
int a[c];
for (int i = 0;i < c;i++) {
cin >> a[i];
cnt[a[i]] = 1;
}
int ans = -cnt[s];
if (c < B) {
for (auto u : dis[s]) {
if (!cnt[u.f])
ans = max(ans, u.s);
}
}
else {
for (int i = 1;i <= n;i++)
d[i] = -1;
d[s] = 0;
for (int i = s;i >= 1;i--) {
if (d[i] >= 0) {
if (!cnt[i])
ans = max(ans, d[i]);
for (auto u : in[i])
d[u] = max(d[u], d[i] + 1);
}
}
}
cout << ans << '\n';
for (int i = 0;i < c;i++)
cnt[a[i]] = 0;
}
}
return 0;
}
