//JAVAIS BESOIN DU HINT :(
#include <bits/stdc++.h>
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define last(a) a[sz(a)-1]
using namespace std;
using namespace std::chrono;
vector<pair<int,bool>> memo;
vector<bool> visited;
vector<vector<int>> neigh;
vector<vector<pair<int,int>>> minsqrt;
vector<bool> mp;
vector<bool> mp2;
int timer=0;
int SQRT=0;
int mnDP2=0;
int c=0;
void dp(int x){
if(visited[x]) return;
visited[x]=true;
for (auto t : neigh[x]) {
vector<pair<int,int>> nw;
dp(t);
int i=0;
for (auto u : minsqrt[t])
{
c++;
if(u.second>=0&&mp2[u.second]==true) continue;
if(sz(nw)>=SQRT) break;
while(sz(nw)<SQRT&&i<SQRT&&minsqrt[x][i].first>u.first+1) {
c++;
if(minsqrt[x][i].second<0||!mp2[minsqrt[x][i].second]) {
nw.push_back(minsqrt[x][i]);
if(minsqrt[x][i].second>=0) mp2[minsqrt[x][i].second]=true;
if(sz(nw)>=SQRT) break;
}
i++;
}
if(sz(nw)>=SQRT) break;
if(u.second>=0) mp2[u.second]=true;
nw.push_back({u.first+1,u.second});
}
while(sz(nw)<SQRT&&i<SQRT) {
if(minsqrt[x][i].second<0||!mp2[minsqrt[x][i].second]) {
nw.push_back(minsqrt[x][i]);
if(minsqrt[x][i].second>=0) mp2[minsqrt[x][i].second]=true;
if(sz(nw)>=SQRT) break;
}
i++;
}
for (i = 0; i < SQRT; i++) {
if(nw[i].second>=0) mp2[nw[i].second]=false;
minsqrt[x][i]={nw[i].first,nw[i].second};
}
}
vector<pair<int,int>> nw;
bool b=false;
for (int i = 0; i < SQRT; i++){
if(!b&&0>minsqrt[x][i].first) {
nw.push_back({0,x});
b=true;
}
if(sz(nw)==SQRT) break;
nw.push_back(minsqrt[x][i]);
if(sz(nw)==SQRT) break;
}
for (int i = 0; i < SQRT; i++) {
minsqrt[x][i]={nw[i].first,nw[i].second};
}
return;
}
pair<int,bool> dp2(int x){
if(memo[x].first>=0) return memo[x];
int mx=0;
bool b=!(mp[x]);
for (auto t : neigh[x]) {
pair<int,bool> d=dp2(t);
if(d.second==false) continue;
b=true;
mx=max(mx,d.first+1);
}
memo[x]={mx,b};
return {mx,b};
}
signed main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
//auto start = high_resolution_clock::now();
int N,M,Q; cin >> N >> M >> Q;
memo.resize(N,{-1,false});
neigh.resize(N);
visited.resize(N,false);
minsqrt.resize(N);
mp.resize(N);
mp2.resize(N,false);
SQRT=sqrt(N)/2;
for (int i = 0; i < N; i++)
{
minsqrt[i].resize(SQRT,{-1e9,-1e9});
}
c=0;
vector<bool> leaf(N,true);
for (int i = 0; i < M; i++)
{
int a,b; cin >> a >> b;
a--; b--;
neigh[b].push_back(a);
leaf[a]=false;
}
for (int i = 0; i < N; i++) dp(i);
//cout << c << "\n";
while (Q--)
{
int T,Y; cin >> T >> Y;
T--;
vector<int> y(Y);
for (int i = 0; i < Y; i++)
{
cin >> y[i];
y[i]--;
mp[y[i]]=true;
}
if(Y>=SQRT){
memo.clear();
memo.resize(N,{-1,false});
pair<int,bool> d=dp2(T);
if(d.second==false) d.first=-1;
cout << d.first << "\n";
}else{
mnDP2=-1e9;
for (int i = 0; i < SQRT; i++)
{
if(minsqrt[T][i].second<0||mp[minsqrt[T][i].second]) continue;
mnDP2=max(minsqrt[T][i].first,mnDP2);
}
cout << max(-1,mnDP2) << "\n";
}
for (int i = 0; i < Y; i++)
{
mp[y[i]]=false;
}
}
/*auto stop = high_resolution_clock::now();
auto duration = duration_cast<seconds>(stop - start);
cout << duration.count() << "s\n";*/
return 0;
}
