#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL_PROJECT
#else
#define cerr \
if (false) cerr
#endif
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(), x.end()
#define ALL(x) begin(x), end(x)
#define FOR(i, a) for (int i = 0; i < (a); i++)
#define SZ(a) (int)(a).size()
typedef pair<int, int> ii;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef tuple<int, int, int> iii;
typedef vector<ll> vll;
const int INF = 1e9;
const ll INFL = 1e18;
const int MOD = 1000000007;
const int sz = 1e5 + 5;
vi adj[sz];
int k;
bool vis[sz];
ii towns[sz][320];
void dfs(int u, int p) {
for (auto v : adj[u]) {
if (v != p) dfs(v, u);
}
vii paths;
for (auto v : adj[u]) {
if (v == p) continue;
for (int i = 0; i < k; ++i) {
if (towns[v][i].s == 0) break;
paths.pb({1 + towns[v][i].f, towns[v][i].s});
}
paths.pb({1, v});
}
sort(all(paths), greater<ii>());
set<int> chosen;
int curr = 0;
int i = 0;
while (curr < k and i < SZ(paths)) {
if (chosen.find(paths[i].s) != chosen.end()) {
i++;
continue;
}
towns[u][curr] = paths[i];
chosen.insert(paths[i].s);
// cerr << paths[i].f << " " << paths[i].s << endl;
i++;
curr++;
}
vis[u] = true;
}
int dfs2(int u, int p, vi& banned) {
auto it = lower_bound(all(banned), u);
int ans = 0;
if (it != banned.end() and *it == u) {
ans = -INF;
}
for (auto v : adj[u]) {
if (v == p) continue;
auto it = lower_bound(all(banned), v);
bool ban = (it != banned.end() and *it == v);
int child = 1 + dfs2(v, u, banned);
if (child == 1 and ban) continue;
ans = max(ans, child);
}
return ans;
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
#ifdef LOCAL_PROJECT
#else
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
#endif
int n, m, q;
cin >> n >> m >> q;
k = sqrt(n);
for (int i = 0; i < m; ++i) {
int s, e;
cin >> s >> e;
adj[e].pb(s);
}
for (int i = n; i >= 1; --i) {
if (vis[i]) continue;
dfs(i, 0);
}
while (q--) {
int t, y;
cin >> t >> y;
vi v(y);
for (int i = 0; i < y; ++i) cin >> v[i];
if (false) {
bool f = false;
for (int i = 0; i < k; ++i) {
if (towns[t][i].s == 0) break;
auto pos = lower_bound(all(v), towns[t][i].s);
if (pos != v.end() and *pos == towns[t][i].s) continue;
cout << towns[t][i].f << endl;
f = true;
break;
}
if (!f) cout << -1 << endl;
} else {
int ans = dfs2(t, 0, v);
if (ans < 0)
cout << -1;
else
cout << ans;
cout << endl;
}
}
}
