// ~~ icebear ~~
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;
template<class T>
bool minimize(T &a, const T &b) {
if (a > b) return a = b, true;
return false;
}
template<class T>
bool maximize(T &a, const T &b) {
if (a < b) return a = b, true;
return false;
}
#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "icebear"
const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll INF = 1e18 + 27092008;
const int N = 2e5 + 5;
const int S = 200;
int n, m, q;
ii dist[S][N], tmp[S];
vector<int> G[N];
int f[N];
void mergeDist(int u, int v) {
int i = 0, j = 0, cur = 0;
while(cur < S) {
if (i < S && f[dist[i][u].se] > 0) {
i++;
continue;
}
if (j < S && f[dist[j][v].se] > 0) {
j++;
continue;
}
if (i < S && dist[i][u].se > 0 && (j == S || dist[i][u].fi > dist[j][v].fi + 1 || dist[j][v].se == 0)) {
tmp[cur++] = dist[i][u];
f[dist[i][u].se] = 1;
i++;
} else if (j < S && dist[j][v].se > 0) {
tmp[cur++] = mp(dist[j][v].fi + 1, dist[j][v].se);
f[dist[j][v].se] = 1;
j++;
} else break;
}
REP(i, cur) dist[i][u] = tmp[i], f[tmp[i].se] = 0;
}
void prepareDist() {
FOR(i, 1, n) {
dist[0][i] = mp(0, i);
for(int v : G[i]) mergeDist(i, v);
}
}
void init(void) {
cin >> n >> m >> q;
FOR(i, 1, m) {
int u, v;
cin >> u >> v;
if (u < v) swap(u, v);
G[u].pb(v);
}
}
void process(void) {
vector<bool> inQuery(n + 5, false);
prepareDist();
while(q--) {
int T, k; cin >> T >> k;
vector<int> nodes(k);
for(int &i : nodes) cin >> i, inQuery[i] = true;
bool haveAns = false;
if (k < S) {
REP(i, S) if (!inQuery[dist[i][T].se]) {
cout << dist[i][T].fi << '\n';
haveAns = true;
break;
}
} else {
FOR(i, 1, n) f[i] = 0;
FOR(i, 1, T) {
for(int v : G[i])
if (!inQuery[v] || (inQuery[v] && f[v] > 0))
maximize(f[i], f[v] + 1);
}
if (f[T] > 0 || !inQuery[T]) {
cout << f[T] << '\n';
haveAns = true;
}
}
if (!haveAns) cout << -1 << '\n';
for(int &i : nodes) inQuery[i] = false;
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
if (fopen(task".inp", "r")) {
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
int tc = 1;
// cin >> tc;
while(tc--) {
init();
process();
}
return 0;
}
