#include <bits/extc++.h>
using namespace std;
using namespace __gnu_pbds;
template<typename T>
using oset = tree<T, null_type, less<T>, rb_tree_tag,
tree_order_statistics_node_update>;
#define rep(i, a, b) for(int i = (a); i < (b); i++)
#define each(a, x) for(auto& a : x)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define over(x) {cout<<x<<'\n'; return;}
#define pb push_back
#define f first
#define s second
typedef long long ll;
typedef long double db;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
mt19937 gen(chrono::steady_clock::now().time_since_epoch().count());
ll rng() { return uniform_int_distribution<ll>(0, INT64_MAX)(gen); }
/*const db PI = atan(1)*4;*/
/*const ll mod = 1e9+7;*/
const ll mod = 998244353;
const int mx=1e5+5, ms=200;
vi adj[mx], radj[mx];
vi qv[mx];
vi qs[mx];
pi dp[mx][ms];
int cnt[mx];
int mn[mx];
int dp2[mx];
int ans[mx];
void solve(int){
rep(i,0,mx){
dp[i][0]={0,-1};
rep(j,1,ms)dp[i][j]={-1,-1};
}
memset(mn, -1, sizeof(mn));
int n, m, q;
cin>>n>>m>>q;
rep(i, 0, m){
int a, b;cin>>a>>b;
a--;b--;
adj[a].pb(b);
radj[b].pb(a);
}
rep(i, 0, q){
int x, s;
cin>>x>>s;
x--;
qs[x].pb(i);
qv[i].resize(s);
rep(j,0,s)cin>>qv[i][j], qv[i][j]--;
}
rep(i, 0, n){
vi p(1,i);
mn[i]=0;
vpi p2;
each(j,radj[i]){
each(k,dp[j]){
if(k.s==-1)break;
if(mn[k.s]==-1) p.pb(k.s);
mn[k.s]=max(mn[k.s], k.f+1);
}
}
p2.resize(sz(p));
rep(j,0,sz(p)) p2[j]={mn[p[j]], p[j]};
sort(all(p2), greater<pi>());
rep(j,0,min(ms, sz(p2)))dp[i][j]=p2[j];
rep(j,0,sz(p))mn[p[j]]=-1;
/*rep(j,0,sz(p))cout<<dp[i][j].f<<' ';cout<<'\n';*/
each(j,qs[i]){
rep(k,0,sz(qv[j]))cnt[qv[j][k]]++;
if(sz(qv[j])<ms){
rep(k,0,ms){
if(cnt[dp[i][k].s]==0){
ans[j]=dp[i][k].f;
break;
}
}
} else {
rep(k,0,i+1){
dp2[k]=-1e9;
if(cnt[k]==0)dp2[k]=0;
each(l,radj[k]){
dp2[k]=max(dp2[k], dp2[l]+1);
}
}
ans[j]=dp2[i]>0?dp2[i]:-1;
}
rep(k,0,sz(qv[j]))cnt[qv[j][k]]--;
}
}
rep(i,0,q)cout<<ans[i]<<'\n';
}
int main(){
cin.tie(0)->sync_with_stdio(0);
cin.exceptions(cin.failbit);
int tc=1;
/*cin>>tc;*/
while(tc--) solve(tc);
return 0;
}
