#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>
#define ull unsigned ll
#define f first
#define s second
#define FOR(i,a,b) for (int i=(a); i<(b); ++i)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) for (int i=(n-1); i>=0; --i)
#define REP1(i,n) FOR(i,1,n+1)
#define ALL(x) x.begin(),x.end()
#define SZ(x) (int)x.size()
#define SQ(x) (x)*(x)
#define MN(a,b) a = min(a,(__typeof__(a))(b))
#define MX(a,b) a = max(a,(__typeof__(a))(b))
#define pb push_back
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#ifdef BALBIT
#define IOS()
#define bug(...) fprintf(stderr,"#%d (%s) = ",__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...);}
#else
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0);
#define endl '\n'
#define bug(...)
#endif
const int iinf = 1<<29;
const ll inf = 1ll<<60;
const ll mod = 1e9+7;
void GG(){cout<<"-1\n"; exit(0);}
ll mpow(ll a, ll n, ll mo = mod){ // a^n % mod
ll re=1;
while (n>0){
if (n&1) re = re*a %mo;
a = a*a %mo;
n>>=1;
}
return re;
}
ll inv (ll b, ll mo = mod){
if (b==1) return b;
return (mo-mo/b) * inv(mo%b) % mo;
}
const int maxn = 1e5+5;
const int BS = 200;
vector<int> tome[maxn];
vector<pii> far[maxn]; // The BS-th farthest nodes from i , {a,b}: farthest distance, node number
bool seen[maxn]; // Temporary array for things in far[i]
int farth[maxn];
signed main(){
IOS();
#ifdef BALBIT
freopen("input.in","r",stdin);
#endif // BALBIT
int n, m, q; cin>>n>>m>>q;
REP(i,m) {
int a, b; cin>>a>>b; tome[b-1].pb(a-1);
}
REP(i,n) {
far[i] = {{-1,i}};
for (int v : tome[i]) {
vector<pii> tmp = far[i]; far[i].clear();
int it = 0;
for (pii x : far[v]) {
while (it != SZ(tmp) && tmp[it].f>= x.f) {
if (!seen[tmp[it].s]) {
seen[tmp[it].s]=1;
far[i].push_back(tmp[it]);
}
++it;
}
if (!seen[x.s]) {
seen[x.s]=1; far[i].push_back(x);
}
}
FOR(j,it,SZ(tmp)) if (!seen[tmp[j].s]) {
far[i].pb(tmp[j]);
seen[tmp[j].s]=1;
}
for (pii x : far[i]) seen[x.s]=0;
while (far[i].size() > BS) far[i].pop_back();
}
for (pii &x : far[i]) {
++x.f;
}
// Make sure to set seen back to 0
}
while (q--) {
int v; cin>>v; --v;
int Y; cin>>Y;
vector<int> vec(Y);
REP(i,Y) {
cin>>vec[i]; seen[--vec[i]] = 1;
}
if (Y < BS) {
bool done = 0;
for (pii &x : far[v]) {
if (!seen[x.s]) {
cout<<x.f<<endl; done = 1; break;
}
}
if (!done) cout<<-1<<endl;
}else{
REP(i,n) {
farth[i] = seen[i]?-n-n:0;
for (int u : tome[i]) {
MX(farth[i], farth[u]+1);
}
}
cout<<max(farth[v],-1)<<endl;
}
REP(i,Y) {
seen[vec[i]] = 0;
}
}
}
