/* * In the name of GOD */
#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
#define F first
#define S second
#define mk make_pair
const int N = 101234, SQ = 323;
pii mx[N][SQ];
pii c[SQ];
bool f[N];
vector <int> in[N], out[N];
int dp[N];
vector <int> dis[N];
void merge (int a, int b) {
int in1 = 0, in2 = 0;
for (int i = 0; i < SQ; i++) {
while (mx[a][in1].S != -1 && f[mx[a][in1].S])
in1++;
while (mx[b][in2].S != -1 && f[mx[b][in2].S])
in2++;
if (mx[b][in2].F == -1)
c[i] = max(mx[a][in1], mk(mx[b][in2].F, mx[b][in2].S));
else
c[i] = max(mx[a][in1], mk(mx[b][in2].F + 1, mx[b][in2].S));
if (c[i].S != -1)
f[c[i].S] = true;
}
for (int i = 0; i < SQ; i++) {
if (c[i].S != -1)
f[c[i].S] = false;
mx[a][i] = c[i];
}
}
int32_t main() {
ios::sync_with_stdio(false);
cin.tie();
cout.tie();
int n, m, q;
cin >> n >> m >> q;
for (int i = 0; i < m; i++) {
int a, b;
cin >> a >> b;
out[a].push_back(b);
in[b].push_back(a);
}
for (int i = 1; i <= n; i++) {
mx[i][0] = {0, i};
for (int j = 1; j < SQ; j++)
mx[i][j] = {-1, -1};
for (int k : in[i])
merge (i, k);
}
while (q--) {
int v, sz;
cin >> v >> sz;
vector <int> wef(sz);
for (int i = 0; i < sz; i++) {
cin >> wef[i];
f[wef[i]] = true;
}
if (sz < SQ) {
for (int i = 0; i < SQ; i++) {
if (mx[v][i].S == -1 || !f[mx[v][i].S]) {
cout << mx[v][i].F << '\n';
break;
}
}
} else {
for (int i = 1; i <= n; i++)
dp[i] = -N;
dp[v] = 0;
for (int i = v - 1; i >= 0; i--)
for (int j : out[i])
dp[i] = max(dp[i], dp[j] + 1);
int ans = -1;
for (int i = 1; i <= n; i++)
if (!f[i])
ans = max(ans, dp[i]);
cout << ans << '\n';
}
for (int i = 0; i < sz; i++) {
f[wef[i]] = false;
}
}
}
