#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define pii pair<int,int>
#define F first
#define S second
vector<pii> ans[100005];
vector<int> adj[100005];
const int bucket = 350;
int dg[100005];
bool sq[100005];
int dp[100005];
int n , m , qq , target;
int read(){
char c;
int a = 0;
while(!(c>='0' && c<='9'))c = getchar();
while( c>='0' && c <= '9') a = 10*a + (c - '0') , c = getchar();
return a;
}
int solve(int i){
if(i == target) return dp[i] = 0;
if(dp[i] != -10000000 ) return dp[i];
for(auto p : adj[i]){
dp[i] = max(dp[i] , solve(p) + 1);
}
return dp[i];
}
int main(){
n = read() , m = read() , qq = read();
for(int i = 0 ; i < n; i ++ ) ans[i].pb(pii(0 , i)) , dg[i] = 0;
for(int i = 0 ; i < m ; i++){
int x = read() , y = read();
adj[x-1].pb(y-1);
dg[y-1]++;
}
queue<int> q;
for(int i = 0 ; i < n; i++) if(dg[i] == 0) q.push(i);
while(!q.empty()){
int u = q.front();
q.pop();
for(int p : adj[u]){
dg[p]--;
vector<pii> a = ans[u], b = ans[p];
ans[p].clear();
int x = 0 , y = 0;
for(int i = 0 ; i < a.size() + b.size() ; i++){
if(x == a.size()){
if(sq[b[y].S] == false)
ans[p].push_back(pii(b[y].F , b[y].S)) , sq[b[y].S] = true;
y++;
}
else if(y == b.size()){
if(sq[a[x].S] == false)
ans[p].push_back(pii(a[x].F + 1 , a[x].S)) , sq[a[x].S] = true;
x++;
}
else{
if(a[x].F +1> b[y].F){
if(sq[a[x].S] == false)
ans[p].push_back(pii(a[x].F + 1 , a[x].S)) , sq[a[x].S] = true;
x++;
}
else{
if(sq[b[y].S] == false)
ans[p].push_back(pii(b[y].F , b[y].S)) , sq[b[y].S] = true;
y++;
}
}
}
a.clear() , b.clear();
while(ans[p].size() >= bucket) sq[ans[p].back().S] = 0 , ans[p].pop_back();
for(int i = 0 ; i < ans[p].size() ; i++) sq[ans[p][i].S] = false;
if(dg[p] == 0) q.push(p);
}
}
while(qq--){
int t = read() , y = read();
t--;
vector<int> w(y);
for(int i = 0 ; i < y ; i ++){
w[i] = read();
sq[w[i] - 1] = 1;
}
int ansj = -1;
if(y < 337){
for(int j = 0 ; j < ans[t].size() ; j++){
if(sq[ans[t][j].S]) continue;
ansj = max(ansj , ans[t][j].F);
}
printf("%d\n" , ansj);
}
else{
for(int i = 0 ; i < n; i++) dp[i] = -10000000;
target = t;
for(int i = 0 ; i <= t ; i++){
if(sq[i]) continue;
solve(i);
}
for(int i = 0 ; i <= t ;i++){
if(sq[i]) continue;
ansj = max(dp[i] , ansj);
}
printf("%d\n" , ansj);
}
for(int i = 0 ; i < y ; i ++){
sq[w[i] - 1] = 0;
}
}
}
