#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define X first
#define Y second
const int N=1e5+5;
const int oo=1e9+1;
int n,m,request,x,y,k;
int a[N],dp[N];
bool IsBusy[N];
vector <int> g[N];
namespace sub1
{
void dfs(int u)
{
if (!IsBusy[u]) dp[u]=0;
else dp[u]=-oo;
for (int v:g[u])
{
if (dp[v]==-1) dfs(v);
dp[u]=max(dp[u],dp[v]+1);
}
}
void solve()
{
while (request--)
{
cin >> x >> k;
for (int j=1;j<=k;j++)
{
cin >> a[j];
IsBusy[a[j]]=true;
}
for (int i=1;i<=n;i++)
dp[i]=-1;
dfs(x);
if (dp[x]<0) dp[x]=-1;
cout << dp[x] << '\n';
for (int j=1;j<=k;j++)
IsBusy[a[j]]=false;
}
}
}
namespace sub3
{
int S;
bool ok,used[N];
vector <pii> mx_dist[N];
vector <pii> MergeDist(vector <pii> A,vector <pii> B)
{
vector <pii> C;
C.clear();
for (int i=0;i<B.size();i++)
B[i].X++;
int l=0;
int r=0;
while (C.size()<S and l<A.size() and r<B.size())
{
if (A[l].X>B[r].X)
{
if (!used[A[l].Y])
{
C.push_back(A[l]);
used[A[l].Y]=true;
}
l++;
}
else
{
if (!used[B[r].Y])
{
C.push_back(B[r]);
used[B[r].Y]=true;
}
r++;
}
}
while (C.size()<S and l<A.size())
{
if (!used[A[l].Y])
{
C.push_back(A[l]);
used[A[l].Y]=true;
}
l++;
}
while (C.size()<S and r<B.size())
{
if (!used[B[r].Y])
{
C.push_back(B[r]);
used[B[r].Y]=true;
}
r++;
}
for (pii j:C)
used[j.Y]=false;
return C;
}
void pre_dfs(int u)
{
mx_dist[u].push_back(make_pair(0,u));
for (int v:g[u])
{
if (mx_dist[v].size()==0) pre_dfs(v);
mx_dist[u]=MergeDist(mx_dist[u],mx_dist[v]);
}
}
void dfs(int u)
{
if (!IsBusy[u]) dp[u]=0;
else dp[u]=-oo;
for (int v:g[u])
{
if (dp[v]==-1) dfs(v);
dp[u]=max(dp[u],dp[v]+1);
}
}
void solve()
{
S=trunc(sqrt(n));
for (int i=1;i<=n;i++)
if (mx_dist[i].size()==0)
pre_dfs(i);
while (request--)
{
cin >> x >> k;
for (int j=1;j<=k;j++)
{
cin >> a[j];
IsBusy[a[j]]=true;
}
if (k>=S)
{
for (int i=1;i<=n;i++)
dp[i]=-1;
dfs(x);
if (dp[x]<0) dp[x]=-1;
cout << dp[x] << '\n';
}
else
{
ok=false;
for (pii j:mx_dist[x])
if (!IsBusy[j.Y])
{
ok=true;
cout << j.X << '\n';
break;
}
if (!ok) cout << -1 << '\n';
}
for (int j=1;j<=k;j++)
IsBusy[a[j]]=false;
}
}
}
int main()
{
ios_base::sync_with_stdio(NULL);
cin.tie(NULL); cout.tie(NULL);
cin >> n >> m >> request;
for (int i=1;i<=m;i++)
{
cin >> x >> y;
g[y].push_back(x);
}
sub3::solve();
}
