#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxN = 1e5 + 4;
int n, m, q, s = 100, a[maxN];
vector<int> E[maxN];
bool block[maxN];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
// freopen(".INP","r",stdin);
// freopen(".OUT","w",stdout);
cin >> n >> m >> q;
for (int i = 1; i <= m; ++i)
{
int u, v; cin >> u >> v;
E[u].push_back(v);
E[v].push_back(u);
}
vector<vector<pair<int,int>>> path_size(n + 1);
vector<int> from(n + 1, -1);
for (int u = 1; u <= n; ++u)
{
path_size[u].push_back({0, u});
vector<int> from_idx;
for (int v : E[u])
{
for (pair<int,int> x : path_size[v])
{
int dist = x.first;
int idx = x.second;
if (from[idx] == -1)
{
from_idx.push_back(idx);
from[idx] = dist + 1;
}
else from[idx] = max(from[idx], dist + 1);
}
}
for (int v : from_idx) path_size[u].push_back({from[v], v});
sort(path_size[u].rbegin(), path_size[u].rend());
while(path_size[u].size() > s) path_size[u].pop_back();
for (int v : from_idx) from[v] = -1;
}
for (int i = 1; i <= q; ++i)
{
int t, y; cin >> t >> y;
for (int j = 1; j <= y; ++j)
{
cin >> a[j];
block[a[j]] = true;
}
int ans = -1;
if (y >= s)
{
vector<int> dp(n + 1, -1);
dp[t] = 0;
for (int u = t; u >= 1; --u)
{
if (dp[u] == -1) continue;
if (!block[u]) ans = max(ans, dp[u]);
for (int v : E[u]) dp[v] = max(dp[v], dp[u] + 1);
}
}
else
{
for (pair<int,int> x : path_size[t])
{
int dist = x.first;
int idx = x.second;
if (!block[idx])
{
ans = max(ans, dist);
break;
}
}
}
cout << ans << "\n";
for (int j = 1; j <= y; ++j) block[a[j]] = false;
}
return 0;
}
