#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pf push_front
#define iter(v, i) for (__typeof__((v).begin()) i = (v).begin(); i != (v).end(); i++)
#define fast_io_without_cstdio ios_base::sync_with_stdio(false), cin.tie(NULL)
#define all(v) (v).begin(), (v).end()
#define rep(i, s, e) for (int i = s; i < e; i++)
// START for segment tree
#define params int p, int L, int R
#define housekeep int mid = (L + R) >> 1, left = p << 1, right = left | 1
// END
#ifdef __linux__
#define gc getchar_unlocked
#define pc putchar_unlocked
#else
#define gc getchar
#define pc putchar
#endif
#if __cplusplus <= 199711L
template<class BidirIt>
BidirIt prev(BidirIt it, typename iterator_traits<BidirIt>::difference_type n = 1) {
advance(it, -n);
return it;
}
template<class ForwardIt>
ForwardIt next(ForwardIt it, typename iterator_traits<ForwardIt>::difference_type n = 1) {
advance(it, n);
return it;
}
#endif
typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef long double ldouble;
const double EPS = 1e-9;
const double PI = 3.141592653589793238462;
template<typename T>
inline T sq(T a) { return a * a; }
//#ifdef LOCAL_MACHINE
//#endif
const int INF = 1e9;
const int MAXN = 1e5 + 5;
const int SIZE = 350;
const ii senti(-1, 0);
struct myds {
ii ar[SIZE];
myds() {
fill(ar, ar + SIZE, senti);
}
void merge(const myds &rhs) {
myds res;
int x = 0, y = 0, pos = 0;
while (pos < SIZE) {
ii elem(senti);
if (x >= SIZE) {
if (y >= SIZE)
break;
elem = rhs.ar[y];
} else if (y >= SIZE) {
elem = ar[x];
} else {
elem = max(ar[x], rhs.ar[y]);
}
while (x < SIZE && ar[x] == elem)
x++;
while (y < SIZE && rhs.ar[y] == elem)
y++;
res.ar[pos++] = elem;
}
(*this) = res;
}
} paths[MAXN];
vi gr[MAXN], rgr[MAXN];
vi bl[MAXN], quer[MAXN];
int dp[MAXN];
int ans[MAXN];
bool exist[MAXN];
int main() {
//freopen("", "r", stdin);
//freopen("", "w", stdout);
int n, m, q;
scanf("%d %d %d", &n, &m, &q);
for (int i = 1; i <= m; i++) {
int u, v;
scanf("%d %d", &u, &v);
gr[u].pb(v);
rgr[v].pb(u);
}
vii heavy;
for (int i = 1; i <= q; i++) {
int t, y;
scanf("%d %d", &t, &y);
ans[i] = -1;
bl[i].resize(y);
for (int j = 0; j < y; j++)
scanf("%d", &bl[i][j]);
if (y < SIZE - 1)
quer[t].pb(i);
else
heavy.pb(mp(t, i));
}
for (int i = 1; i <= n; i++) {
paths[i].ar[0] = mp(-1, i);
for (auto v : rgr[i]) {
paths[i].merge(paths[v]);
}
for (int j = 0; j < SIZE; j++) {
if (paths[i].ar[j].se != 0)
paths[i].ar[j].fi++;
}
for (auto it : quer[i]) {
for (auto el : bl[it])
exist[el] = true;
int res = -1;
for (int j = 0; j < SIZE; j++) {
if (!exist[paths[i].ar[j].se]) {
res = paths[i].ar[j].fi;
break;
}
}
for (auto el : bl[it])
exist[el] = false;
ans[it] = res;
}
}
for (auto it : heavy) {
for (auto el : bl[it.se])
exist[el] = true;
int t = it.fi;
fill(dp, dp + MAXN, -INF);
int mx = -1;
dp[t] = 0;
for (int u = t; u >= 1; u--) {
for (auto v : gr[u])
dp[u] = max(dp[u], dp[v] + 1);
if (!exist[u] && dp[u] > mx)
mx = dp[u];
}
ans[it.se] = mx;
for (auto el : bl[it.se])
exist[el] = false;
}
for (int i = 1; i <= q; i++) {
printf("%d\n", ans[i]);
}
return 0;
}
