#include<bits/stdc++.h>
using namespace std;
bool M1;
#define PI 3.14159265358979323846
#define sz(a) (int)a.size()
#define all(x) x.begin(),x.end()
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define se second
#define fi first
#define ffi fi.fi
#define sfi se.fi
#define sse se.se
#define fse fi.se
#define lt(i, c, d) for(int i = c; i <= d; ++i)
#define fl(i, c, d) for(int i = d; i >= c; --i)
#define pb push_back
#define emb emplace_back
#define emf emplace_front
#define em emplace
#define look_memory cerr<<abs(&M2-&M1)/1024.0/1024<<'\n'
#define look_time cerr << "TIME : " << clock() * 0.001 << "s" <<'\n'
const int N=1e6+5,lg=30,mod=1e9+7,inf=2e9,block=400;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int u,int v){
return u+rd()%(v-u+1);
}
int dx[]={1,0,-1,0,1,1,-1,-1};
int dy[]={0,-1,0,1,1,-1,1,-1};
int node,edge,query,dist[N];
vector<int>ver[N];
bool k[N],vis[N];
int giailon(int u){
for(int i=1;i<=node;++i)dist[i]=-inf;
dist[u]=0;
int ans=-1;
for(int i=u;i>=1;--i){
for(auto v:ver[i]){
dist[i]=max(dist[i],dist[v]+1);
}
}
for(int i=1;i<=node;++i)
if(!k[i])
ans=max(ans,dist[i]);
return ans;
}
vector<ii>dp[N];
vector<ii>merge(vector<ii>&a,vector<ii>b){
vector<ii>ans;
int i=0,j=0;
for(auto &x:b)x.fi++;
while(i<sz(a)&&j<sz(b)&&sz(ans)<=block){
if(vis[a[i].se]){
++i;
continue;
}
if(vis[b[j].se]){
++j;
continue;
}
if(a[i].fi>b[j].fi){
ans.emb(a[i]);
vis[a[i].se]=true;
++i;
}
else{
ans.emb(b[j]);
vis[b[j].se]=true;
++j;
}
}
while(i<sz(a)&&sz(ans)<=block){
if(vis[a[i].se]){
++i;
continue;
}
ans.emb(a[i]);
vis[a[i].se]=true;
++i;
}
while(j<sz(b)&&sz(ans)<=block){
if(vis[b[j].se]){
++j;
continue;
}
{
ans.emb(b[j]);
vis[b[j].se]=true;
++j;
}
}
for(auto x:a)vis[x.se]=false;
for(auto x:b)vis[x.se]=false;
return ans;
}
void prenho(){
for(int i=1;i<=node;++i){
if(sz(dp[i])<block)
dp[i].emb(0,i);
for(int v:ver[i]){
dp[v]=merge(dp[v],dp[i]);
// if(v==1)cout <<v<<" ";
// cout <<i<<" "<<v<<'\n';
}
}
}
int giainho(int u){
for(auto x:dp[u])
if(!k[x.se])return x.fi;
return -1;
}
bool M2;
void solve(){
cin >> node >>edge>>query;
// cout <<edge<<'\n';
for(int i=1;i<=edge;++i){
int u,v;
cin >> u >> v;
ver[u].emb(v);
}
prenho();
// for(auto x:dp[1])cout <<x.fi<<" "<<x.se<<'\n';
while(query--){
int t,y;
cin >> t >> y;
vector<int>res(y);
for(auto &x:res){
cin >> x;
k[x]=true;
}
if(y>=block)
cout <<giailon(t)<<'\n';
else cout<<giainho(t)<<'\n';
for(auto &x:res){
k[x]=false;
}
}
}
main()
{
srand(time(0));
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
#define task "aws"
if(fopen(task".inp","r")){
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
int t=1;
// cin >> t;
while(t--){
solve();
}
look_memory;
look_time;
}
