//#include<i_am_noob_orz>
#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
#define ll long long
//#define int ll
#define ull unsigned long long
#define pii pair<int,int>
#define X first
#define Y second
#define mod ((ll)1e9+7)
#define pb push_back
#define mp make_pair
#define abs(x) ((x)>0?(x):(-(x)))
#define F(n) Fi(i,n)
#define Fi(i,n) Fl(i,0,n)
#define Fl(i,l,n) for(int i=l;i<n;i++)
#define memres(a) memset(a,0,sizeof(a))
#define all(a) a.begin(),a.end()
#define sz(a) ((int)a.size())
#define ceiling(a,b) (((a)+(b)-1)/(b))
#define endl '\n'
#define bit_count(x) __builtin_popcountll((x))
#define ykh mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define jimmy_is_kind false
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> rbtree;
//#define LOCAL
#ifdef LOCAL
#define bug(...) cerr<<"#"<<__LINE__<<' '<<#__VA_ARGS__<<"- ", _do(__VA_ARGS__)
template<typename T> void _do(T && x) {cerr<<x<<endl;}
template<typename T, typename ...S> void _do(T && x, S&&...y) {cerr<<x<<", "; _do(y...);}
#define IOS()
#else
#define IOS() ios_base::sync_with_stdio(0), cin.tie(0)
#define endl '\n'
#define bug(...)
#endif
int add(int a,int b){return(a+b>=mod?a+b-mod:a+b);}
int sub(int a,int b){return(a<b?a+mod-b:a-b);}
int po(int a,int b){
if(b==0)return 1;
if(b==1)return(a%mod);
int tem=po(a,b/2);
if(b&1)return(((tem*tem)%mod)*a)%mod;
else return(tem*tem)%mod;
}
int GCD(int a,int b){
int x=0;
int ra,rb;
while(a&&b){
if(((a&1)==0)&&((b&1)==0)){
a>>=1,b>>=1,x++;
}
else if((a^b)&1){
if(a&1)b>>=1;
else a>>=1;
}
else{
ra=abs(a-b),rb=min(a,b);
a=ra,b=rb;
}
}
return max(a,b)<<x;
}
int gcd(int a,int b){if(b==0)return a;return gcd(b,a%b);}
vector<int> g[100010],rg[100010],topo,rtopo;
vector<pair<pii,vector<int> > > qt1,qt2;
int n,b,d[100010],o[100010],y,in[100010],rin[100010];
vector<vector<pii> >dp(100010,vector<pii>(350,{0,0}));
bool vis[100010],used[100010];
void bfs(int x){
F(n)d[i]=-1;
queue<int> q;
q.push(x);
d[x]=0;
int p0=0;
while(rtopo[p0]!=x)p0++;
while(p0<n){
int p=rtopo[p0];
if(d[p]!=-1){
for(int u:rg[p]){
d[u]=max(d[u],d[p]+1);
}
}
p0++;
}
}
signed main(){
IOS();
int m,q;
cin>>n>>m>>q;
b=sqrt(n);
F(m){
int x,y;
cin>>x>>y;
--x,--y;
g[x].pb(y);
rg[y].pb(x);
in[y]++;
rin[x]++;
}
F(q){
int x,y;
cin>>x>>y;
--x;
vector<int> tv;
Fi(j,y){
int tx;
cin>>tx;
--tx;
tv.pb(tx);
}
if(y>b)qt1.pb({{x,i},tv});
else qt2.pb({{x,i},tv});
}
queue<int> qu;
F(n){
if(in[i]==0){
qu.push(i);
}
}
while(!qu.empty()){
int p=qu.front();qu.pop();
topo.pb(p);
for(int u:g[p]){
in[u]--;
if(in[u]==0)qu.push(u);
}
}
while(!qu.empty())qu.pop();
F(n){
if(rin[i]==0){
qu.push(i);
}
}
while(!qu.empty()){
int p=qu.front();qu.pop();
rtopo.pb(p);
for(int u:rg[p]){
rin[u]--;
if(rin[u]==0)qu.push(u);
}
}
for(auto node:qt1){
bfs(node.X.X);
for(int i:node.Y)d[i]=-1;
int ans=-1;
F(n)ans=max(ans,d[i]);
o[node.X.Y]=ans;
}
memres(used);
for(int p:topo){
vector<pii> v,tv;
bug(p,sz(rg[p]));
for(int u:rg[p]){
int p0=0,p1=0;
while(p0<sz(v)&&p1<sz(dp[u])&&sz(tv)<b+1){
if(v[p0].X>dp[u][p1].X+1){
if(!used[v[p0].Y]){
used[v[p0].Y]=1;
tv.pb({v[p0].X,v[p0].Y});
}
p0++;
}
else{
if(!used[dp[u][p1].Y]){
used[dp[u][p1].Y]=1;
tv.pb({dp[u][p1].X+1,dp[u][p1].Y});
}
p1++;
}
}
if(sz(tv)<b+1){
while(p0<sz(v)&&sz(tv)<b+1){
if(!used[v[p0].Y]){
used[v[p0].Y]=1;
tv.pb({v[p0].X,v[p0].Y});
}
p0++;
}
while(p1<sz(dp[u])&&sz(tv)<b+1){
if(!used[dp[u][p1].Y]){
used[dp[u][p1].Y]=1;
tv.pb({dp[u][p1].X+1,dp[u][p1].Y});
}
p1++;
}
}
swap(tv,v);
for(pii pi:v){
used[pi.Y]=0;
}
tv.clear();
}
if(sz(v)<b+1){
v.pb({0,p});
}
F(sz(v))bug(v[i].X,v[i].Y);
swap(dp[p],v);
}
for(auto node:qt2){
int ans=-1;
for(int i:node.Y)used[i]=1;
for(pii pi:dp[node.X.X]){
if(!used[pi.Y]){
ans=pi.X;
break;
}
}
for(int i:node.Y)used[i]=0;
o[node.X.Y]=ans;
}
F(q)cout<<o[i]<<endl;
return 0;
}
