/**
* Solution by Charles Ran (polarity.sh)
* Date: 2025-06-10
* Contest: JOI 2018
* Problem: bitaro
**/
#include <bits/stdc++.h>
using namespace std;
using ull = unsigned long long;
using ll = long long;
using vi = vector<int>;
using vl = vector<ll>;
using pii = pair<int, int>;
#define pb push_back
#define rep(i, a, b) for(int i = (a); i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
const int MAX_N = 1e5 + 1;
const ll MOD = 1e9 + 7;
/** TOOL: Debug
* PURPOSE: Prints various data types to terminal
* SOURCE: tourist
*/
template <typename A, typename B>
string to_string(pair<A, B> p);
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
string to_string(const string& s) {
return '"' + s + '"';
}
string to_string(const char* s) {
return to_string((string) s);
}
string to_string(bool b) {
return (b ? "true" : "false");
}
string to_string(vector<bool> v) {
bool first = true;
string res = "{";
for (int i = 0; i < static_cast<int>(v.size()); i++) {
if (!first) {
res += ", ";
}
first = false;
res += to_string(v[i]);
}
res += "}";
return res;
}
template <size_t N>
string to_string(bitset<N> v) {
string res = "";
for (size_t i = 0; i < N; i++) {
res += static_cast<char>('0' + v[i]);
}
return res;
}
template <typename A>
string to_string(A v) {
bool first = true;
string res = "{";
for (const auto &x : v) {
if (!first) {
res += ", ";
}
first = false;
res += to_string(x);
}
res += "}";
return res;
}
template <typename A, typename B>
string to_string(pair<A, B> p) {
return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
cerr << " " << to_string(H);
debug_out(T...);
}
void solve(){
int n, m, q; cin >> n >> m >> q;
vector<vi> children(n);
vi parcount(n, 0);
rep(i, 0, m){
int a, b; cin >> a >> b;
--a; --b;
children[b].pb(a);
parcount[a]++;
}
int rt = sqrt(n);
vector<vector<pii>> longest(n);
vector<bool> has(n, false);
function<void(int)> dfs;
dfs = [&](int x){
for (int node : children[x]){
dfs(node);
}
int mm = children[x].size();
vi at(mm, 0);
int added = 0;
vi did;
while (added < rt){
int mx = -100;
int mxi = -1;
int mxx = -1;
rep(i, 0, mm){
int node = children[x][i];
if (at[i] == longest[node].size()) continue;
auto [l, xx] = longest[node][at[i]];
if (has[xx]){
at[i]++;
--i;
continue;
}
if (l > mx){
mx = l;
mxi = i;
mxx = xx;
}
}
if (mx == -100) break;
longest[x].pb({mx + 1, mxx});
has[mxx] = true;
did.pb(mxx);
at[mxi]++;
added++;
}
for (int node : did){
has[node] = false;
}
if (added < rt){
longest[x].pb({0, x});
}
};
rep(i, 0, n){
if (parcount[i] != 0) continue;
dfs(i);
}
function<int(int, vector<bool>&)> query;
query = [&](int x, vector<bool>& cannot){
int ans = -1;
for (int node : children[x]){
int mx = query(node, cannot);
if (mx == -1) continue;
ans = max(ans, 1 + mx);
}
if (!cannot[x]){
ans = max(ans, 0);
}
return ans;
};
vector<bool> cannot(n, false);
rep(i, 0, q){
int a, y; cin >> a >> y;
--a;
vi cant;
rep(j, 0, y){
int x; cin >> x;
--x;
cannot[x] = true;
cant.pb(x);
}
int ans = -1;
if (y < rt){
rep(j, 0, longest[a].size()){
auto [l, x] = longest[a][j];
if (cannot[x]) continue;
ans = l;
break;
}
} else {
ans = query(a, cannot);
}
for (int x : cant){
cannot[x] = false;
}
cout << ans << endl;
}
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
solve();
return 0;
}
