#include<bits/stdc++.h>
#define X first
#define Y second
#define PB push_back
using namespace std;
const int maxn = 1e5 + 7;
const int oo = 1e9;
const int K = 100;
typedef pair < int, int > pii;
vector < pii > furthest[maxn];
vector < int > v[maxn], r[maxn];
int dis[maxn], busy[maxn], n, m, q, uso[maxn], cnt[maxn];
void spoji(int x)
{
priority_queue < pii > Q;
for(int y : r[x])
{
cnt[y] = 0;
Q.push({furthest[y][0].X, y});
}
while((!Q.empty()) && furthest[x].size() < K)
{
int ind = Q.top().Y;
if(!uso[furthest[ind][cnt[ind]].Y])
{
uso[furthest[ind][cnt[ind]].Y] = 1;
furthest[x].PB(furthest[ind][cnt[ind]]);
}
Q.pop();
cnt[ind]++;
if(cnt[ind] < (int)furthest[ind].size())
Q.push({furthest[ind][cnt[ind]].X, ind});
}
for(pii &tmp : furthest[x])
uso[tmp.Y] = 0, tmp.X++;
if(furthest[x].size() < K)
furthest[x].PB({0, x});
}
void precompute()
{
for(int i = 1;i <= n;i++)
spoji(i);
}
int lonhoncan(int x)
{
for(int i = 1;i <= n;i++)
dis[i] = -oo;
dis[x] = 0;
int res = -1;
for(int i = x; i >= 1 ; i--)
{
for(int j : v[i])
dis[i] = max(dis[i], dis[j] + 1);
if(!busy[i])
res = max(res, dis[i]);
}
return res;
}
int main()
{
//freopen("bitaro.inp", "r", stdin);
cin >> n >> m >> q;
while (m--)
{
int x, y;
cin >> x >> y;
v[x].PB(y);
r[y].PB(x);
}
precompute();
while (q--)
{
int st;
cin >> st;
int n_people_busy;
cin >> n_people_busy;
vector < int > tmp;
while(n_people_busy--)
{
int x; cin >> x;
tmp.PB(x); busy[x] = 1;
}
if(tmp.size() >= K)
cout << lonhoncan(st) << '\n';
else{
int res = -1;
for(pii ttm : furthest[st]) // K thang lon nhat cua st
if(!busy[ttm.Y]) res = max(res, ttm.X);
cout << res << '\n';
}
for(int x : tmp) busy[x] = 0;
}
return 0;
}
