#include <bits/stdc++.h>
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(0);
#define FILE_NAME "BITARO"
#define ll long long
#define pb push_back
#define fi first
#define se second
using namespace std;
const int MAXN = 100001;
int n, m, q;
int d[MAXN], q_t[MAXN];
vector<int> adj[MAXN];
vector<bool> busy[MAXN];
void Dijkstra(int uStart)
{
memset(d, -0x3F, sizeof(d));
priority_queue<pair<int, int> > pq;
d[uStart] = 0;
pq.push({0, uStart});
while(!pq.empty()) {
int u = pq.top().second;
int du = pq.top().first;
pq.pop();
if (du != d[u])
continue;
for (int v : adj[u]) {
if (d[v] < d[u]+1) {
d[v] = d[u]+1;
pq.push({d[v], v});
}
}
}
}
int main()
{
FAST_IO;
// freopen(FILE_NAME".INP", "r", stdin);
// freopen(FILE_NAME".OUT", "w", stdout);
cin >> n >> m >> q;
for (int i = 1; i <= m; ++i) {
int u, v;
cin >> u >> v;
adj[v].push_back(u);
}
for (int i = 1; i <= q; ++i) {
int t, y;
cin >> t >> y;
q_t[i] = t;
busy[i].resize(n+1, false);
for (int j = 1; j <= y; ++j) {
int c;
cin >> c;
busy[i][c] = true;
}
}
for (int i = 1; i <= q; ++i) {
Dijkstra(q_t[i]);
int res = 0;
for (int v = 1; v <= n; ++v)
if (!busy[i][v])
res = max(res, d[v]);
if (res == 0 && busy[i][q_t[i]])
res = -1;
cout << res << '\n';
}
return 0;
}
