#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
const int K = 250;
const int MAXN = 100000;
vector <int> graf[MAXN+5];
vector <int> rgraf[MAXN+5];
bool moze[MAXN+5];
int dp[MAXN+5];
pair <int, int> dists[MAXN+5][K+20];
int sz[MAXN+5];
bool used[MAXN+5];
int n;
int resi(int root){
for(int i=1; i<=n; i++) dp[i] = -1;
int mx = -1;
for(int i=root; i>=1; i--){
dp[i] = -n;
if(i == root) dp[i] = 0;
for(auto c : rgraf[i]) if(c <= root) dp[i] = max(dp[i], dp[c] + 1);
if(moze[i]) mx = max(mx, dp[i]);
}
return mx;
}
pair <int, int> temp[2*MAXN+5];
int main(){
ios_base::sync_with_stdio(false), cin.tie(0);
cout.precision(10);
cout << fixed;
int m, qr;
cin >> n >> m >> qr;
for(int i=1; i<=m; i++){
int a, b;
cin >> a >> b;
graf[b].push_back(a);
rgraf[a].push_back(b);
}
for(int i=1; i<=n; i++) moze[i] = 1;
for(int i=1; i<=n; i++){
for(auto c : graf[i]){
int ts = 0;
int j = 1;
for(int k=1; k<=sz[c]; k++){
pair <int, int> x = dists[c][k];
while(j <= sz[i] && dists[i][j].first >= x.first + 1){
temp[++ts] = dists[i][j];
j++;
}
temp[++ts] = {x.first + 1, x.second};
}
while(j <= sz[i]){
temp[++ts] = dists[i][j];
j++;
}
sz[i] = 0;
for(int g=1; g<=ts; g++){
pair <int, int> c = temp[g];
if(sz[i] > K) break;
if(used[c.second]) continue;
used[c.second] = 1;
dists[i][++sz[i]] = {c.first, c.second};
}
for(int g=1; g<=ts; g++) used[temp[g].second] = 0;
}
dists[i][++sz[i]] = {0, i};
}
for(int qrr=1; qrr<=qr; qrr++){
int root;
cin >> root;
int cnt;
cin >> cnt;
vector <int> vec;
for(int i=1; i<=cnt; i++){
int x;
cin >> x;
vec.push_back(x);
moze[x] = 0;
}
if(cnt <= K){
int mx = -1;
for(int k=1; k<=sz[root]; k++) if(moze[dists[root][k].second]) mx = max(mx, dists[root][k].first);
cout << mx << "\n";
}
else{
cout << resi(root) << "\n";
}
for(auto c : vec) moze[c] = 1;
}
return 0;
}
