#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define pa pair<int, int>
#define pall pair<ll, int>
#define fi first
#define se second
#define TASK "test"
#define all(x) x.begin(), x.end()
using namespace std;
template<typename T1, typename T2> bool mini (T1 &a, T2 b) {if(a > b) a = b; else return 0; return 1;}
template<typename T1, typename T2> bool maxi (T1 &a, T2 b) {if(a < b) a = b; else return 0; return 1;}
const int MOD = 1e9 + 7;
const int LOG = 20;
const int maxn = 2e5 + 7;
const int oo = 1e9 + 69;
const int sz = 320;
int n, m, q, u, v, t, y, c, id[maxn], d[maxn];
bool vis[maxn];
pa f[sz][maxn], cur[sz];
vector<int> g[maxn], topo, arc[maxn];
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
//freopen(TASK".inp", "r", stdin);
//freopen(TASK".out", "w", stdout);
cin>>n>>m>>q;
while(m--) {
cin>>u>>v;
g[u].pb(v);
arc[v].pb(u);
}
fill_n(vis, n + 1, 0);
for(int i = 1; i <= n; i++)
for(int j = 0; j < sz; j++) f[j][i] = (j == 0 ? make_pair(0, i):make_pair(-oo, -1));
for(auto u = 1; u <= n; u++) {
for(auto v:g[u]) {
fill_n(cur, sz, make_pair(-oo, -1));
for(int id = 0, i = 0, j = 0; (id < sz && (i < sz || j < sz));) {
auto a = (i >= sz ? make_pair(-1, -1):make_pair(f[i][u].fi + 1, f[i][u].se)), b = (j >= sz ? make_pair(-1, -1):f[j][v]);
if((a.se != -1 && vis[a.se]) && (b.se != -1 && !vis[b.se])) {
cur[id++] = b;
vis[b.se] = 1;
i++;
j++;
} else if((a.se != -1 && !vis[a.se]) && (b.se != -1 && vis[b.se])) {
cur[id++] = a;
vis[a.se] = 1;
i++;
j++;
} else if((a.se != -1 && vis[a.se]) && (b.se != -1 && vis[b.se])) {
i++;
j++;
} else {
if(a.fi < b.fi) {
cur[id++] = b;
vis[b.se] = 1;
j++;
} else {
cur[id++] = a;
vis[a.se]= 1;
i++;
}
}
}
for(int id = 0; id < sz; id++) {
f[id][v] = cur[id];
if(cur[id].se != -1) vis[cur[id].se] = 0;
}
}
}
// for(int i = 0; i < sz; i++) cout<<f[i][5].fi<<" "<<f[i][5].se<<"\n";
fill_n(id, n + 1, 0);
for(int k = 1; k <= q; k++) {
cin>>t>>y;
for(int i = 0; i < y; i++) {
cin>>c;
id[c] = k;
}
if(y >= sz) {
fill_n(d, n + 1, -1);
d[t] = 0;
int ans = -1;
if(id[t] != k) ans = 0;
bool ok = 0;
for(int u = t; u >= 1; u--) {
if(d[u] == -1) continue;
for(auto v:arc[u]) {
maxi(d[v], d[u] + 1);
if(id[v] != k) maxi(ans, d[v]);
}
}
cout<<ans<<"\n";
} else {
int ans = -1;
for(int i = 0; i < sz; i++) {
int u = f[i][t].se;
if(u == -1 || id[u] == k || u > t) continue;
maxi(ans, f[i][t].fi);
}
cout<<ans<<"\n";
}
}
return 0;
}
