#include<cstdio>
#include<cstdlib>
#include<iostream>
#include<vector>
#include<queue>
#include<bitset>
#include<string>
#include<stack>
#include<set>
#include<unordered_set>
#include<map>
#include<unordered_map>
#include<cstring>
#include<complex>
#include<cmath>
#include<iomanip>
#include<numeric>
#include<algorithm>
#include<list>
#include<functional>
#include<cassert>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a));
#define MEM_1(a) memset((a),-1,sizeof(a));
#define ALL(a) a.begin(),a.end()
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<ld, ld> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int,int,int,int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const ll MOD = 1000000007;
ll POW(ll a, ll b, ll MMM = MOD) {ll ret=1; for(;b;b>>=1,a=(a*a)%MMM)if(b&1)ret=(ret*a)% MMM; return ret; }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
ll lcm(ll a, ll b) { if (a == 0 || b == 0)return a + b; return a*(b / gcd(a, b)); }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };
const int sq=300;
Vi v[100001];
int d[100001];
bool chk[100001],cc[100001];
Pi tmp[sq+5];
VPi res[100001];
int n,m,q;
void merge(VPi &a,VPi &b)
{
int c=0,N=a.size(),M=b.size(),i=0,j=0;
while(c<=sq && i<N && j<M)
{
if(cc[a[i].Y])
{
i++;
continue;
}
if(cc[b[j].Y])
{
j++;
continue;
}
if(a[i].X>b[j].X+1)
{
tmp[c++]=mp(a[i].X,a[i].Y);
cc[a[i].Y]=1;
i++;
}
else
{
tmp[c++]=mp(b[j].X+1,b[j].Y);
cc[b[j].Y]=1;
j++;
}
}
while(c<=sq && i<N)
{
if(cc[a[i].Y])
{
i++;
continue;
}
tmp[c++]=mp(a[i].X,a[i].Y);
cc[a[i].Y]=1;
i++;
}
while(c<=sq && j<M)
{
if(cc[b[j].Y])
{
j++;
continue;
}
tmp[c++]=mp(b[j].X+1,b[j].Y);
cc[b[j].Y]=1;
j++;
}
a.clear();
fup(i,0,c-1,1)
{
a.pb(tmp[i]);
cc[tmp[i].Y]=0;
}
}
int main() {
scanf("%d%d%d",&n,&m,&q);
fup(i,0,m-1,1)
{
int x,y;
scanf("%d%d",&x,&y);
v[y].pb(x);
}
fup(i,1,n,1)
{
res[i].pb(mp(0,i));
for(int next:v[i])merge(res[i],res[next]);
}
while(q--)
{
Vi vv;
int x,k;
scanf("%d%d",&x,&k);
vv.resize(k);
fup(i,0,k-1,1)
{
scanf("%d",&vv[i]);
chk[vv[i]]=1;
}
if(k>=sq)
{
fup(i,1,n,1)d[i]=-INF;
d[x]=0;
int ans=-1;
fdn(i,x,1,1)
{
if(!chk[i])ans=max(ans,d[i]);
for(int y:v[i])d[y]=max(d[y],d[i]+1);
}
printf("%d\n",ans);
}
else
{
int ans=-1;
for(auto p:res[x])
{
if(!chk[p.Y])ans=max(ans,p.X);
}
printf("%d\n",ans);
}
fup(i,0,k-1,1)chk[vv[i]]=0;
}
}
