#include <bits/stdc++.h>
using namespace std;
const int inf = -1e9;
const int mxN = 1e5 + 10;
const int mxB = 343;
vector<vector<int>> Query[mxN];
vector<int> adj[mxN], radj[mxN];
int dist[mxB][mxN];
signed main(){
ios::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
int n, m, q;
cin >> n >> m >> q;
vector<int> ans(q + 1, -1);
int block_size = sqrt(n + 1) + 1;
for(int i = 0, u, v; i < m; ++i){
cin >> u >> v; --u, --v;
adj[u].push_back(v);
radj[v].push_back(u);
}
vector<int> dp(n + 1, inf);
auto dfs = [&](auto &self, int u, int x) -> int {
if(u > x) return inf;
if(u == x) return 0;
if(dp[u] != inf) return dp[u];
int ans = inf;
for(auto it : adj[u]){
ans = max(ans, self(self, it, x) + 1);
}
return dp[u] = ans;
};
auto get = [&](int l, int r, int x) -> int {
int cans = -1;
for(int i = l; i <= r;){
if(i % block_size == 0 && i + block_size - 1 <= r){
cans = max(cans, dist[i / block_size][x]);
i += block_size;
}else{
cans = max(cans, dfs(dfs, i, x));
i += 1;
}
}
return cans;
};
auto process = [&](int x) -> void {
dp = vector<int>(n + 1, inf);
for(auto cur : Query[x]){
int cur_ans = -1;
for(int j = 0; j < (int) cur.size() - 2; ++j){
int l = cur[j] + 1, r = cur[j + 1] - 1;
if(l <= r){
cur_ans = max(cur_ans, get(l, r, x));
}
}
ans[cur.back()] = cur_ans;
}
};
for(int i = 0, block = 0; i < n; i += block_size, block += 1){
int j = i + block_size - 1;
priority_queue<pair<int, int>> pq;
for(int k = 1; k <= n; ++k){
dist[block][k] = -1;
}
for(int k = i; k <= j; ++k){
pq.push({0, k});
dist[block][k] = 0;
}
while(pq.size()){
auto [d, u] = pq.top();
pq.pop();
for(auto v : adj[u]){
if(dist[block][v] < d + 1){
dist[block][v] = d + 1;
pq.push({d + 1, v});
}
}
}
}
for(int i = 1, x, y; i <= q; ++i){
cin >> x >> y; --x;
vector<int> banned = {-1};
int mx = 0;
for(int j = 0, vrtx; j < y; ++j){
cin >> vrtx; --vrtx;
if(vrtx <= x){
banned.push_back(vrtx);
}
mx = max(mx, vrtx);
}
if(mx > x){
banned.push_back(mx);
}else{
banned.push_back(n);
}
sort(banned.begin(), banned.end());
banned.push_back(i);
Query[x].push_back(banned);
}
for(int i = 0; i < n; ++i){
process(i);
}
for(int i = 1; i <= q; ++i) cout << ans[i] << "\n";
return 0;
}
