#include <bits/stdc++.h>
using namespace std;
#define FastIO ios_base::sync_with_stdio(0);cin.tie(nullptr);
#define MULTEST int t;cin >> t;while (t--) solve();
#define rf(__abc__) freopen(__abc__".inp","r",stdin);freopen(__abc__".out","w",stdout);
const int mod = 1e9 + 7;
long long pw(long long x,long long y) {
if (y == 0) return 1;
if (y % 2 == 0) {
long long a = pw(x,y/2);
return a*a%mod;
} else {
long long a = pw(x,y - 1);
return a*x%mod;
}
}
int add(int x,int y) {
x += y;
if (x >= mod) x -= mod;
return x;
}
int subtract(int x,int y) {
x -= y;
if (x < 0) x += mod;
return x;
}
int mul(long long x,int y) {
x *= y;
if (x >= mod) x %= mod;
return x;
}
///Code goes here
const int can = 300;
int distinct = 0;
int n,m,q;
vector <int> adj[100009];
void input() {
cin >> n >> m >> q;
for (int i = 1;i <= m;i++) {
int u,v;cin >> u >> v;
adj[u].push_back(v);
}
}
//dp
vector <pair<int,int>> dp[100001];
int exist[100009];
vector <pair<int,int>> mergesort(vector <pair<int,int>>& left,vector <pair<int,int>>& right) {
vector <pair<int,int>> ret;
int lpt = 0,rpt = 0;
while (lpt < left.size() && rpt < right.size()) {
if (left[lpt].first > right[rpt].first) {
ret.push_back(left[lpt++]);
} else {
ret.push_back(right[rpt++]);
}
}
for (;lpt < left.size();lpt++) ret.push_back(left[lpt]);
for (;rpt < right.size();rpt++) ret.push_back(right[rpt]);
return ret;
}
void predp() {
for (int i = 1;i <= n;i++) {
dp[i].push_back({-1,i});
for (int j = 1;j < can;j++) dp[i].push_back({-1e9,n + 1});
}
for (int ver = 1;ver <= n;ver++) {
for (int i = 0;i < can;i++) dp[ver][i].first++;
for (auto des : adj[ver]) {
//ver -> des
vector <pair<int,int>> intermediate = mergesort(dp[ver],dp[des]);
distinct++;
int chosen = 0;
for (auto value : intermediate) if (exist[value.second] != distinct) {
exist[value.second] = distinct;
dp[des][chosen] = value;
chosen++;
if (chosen == can) break;
}
}
}
}
//query processing
bool visited[100009],busy[100009];
int dp2[100009];
int caldp(int node) {
if (visited[node]) return dp2[node];
visited[node] = 1;
dp2[node] = (busy[node] ? -1e9 : 0);
for (auto x : adj[node]) {
dp2[node] = max(dp2[node],caldp(x) + 1);
}
return dp2[node];
}
void solve() {
int root,num;cin >> root >> num;
vector <int> record(num + 1);
for (int i = 1;i <= num;i++) {
cin >> record[i];
busy[record[i]] = 1;
}
if (num >= can) {
for (int i = 1;i <= n;i++) visited[i] = dp2[i] = 0;
cout << caldp(root) << '\n';
} else {
for (int i = 0;i < can;i++) if (!busy[dp[root][i].second]) {
cout << max(dp[root][i].first,-1) << '\n';
break;
}
}
for (int i = 1;i <= num;i++) busy[record[i]] = 0;
}
int main() {
//rf("");
FastIO
//MULTEST
//preprocessing
input();
predp();
//answer queries
while (q--) solve();
return 0;
}
