// #pragma GCC optimize("O3")
// #pragma GCC target("avx2")
#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
const int MAXN = 1e5;
const int MAXrtn = 80;
int n, m, q;
bool inactive[MAXN];
pii precomp[MAXN][MAXrtn]; // dist, node
int rtn = 80;
vector<int> edges[MAXN];
int dp[MAXN];
int posses[MAXN];
bool vis[MAXN];
void make() {
for (int i = 0; i < n; i++) {
fill(precomp[i], precomp[i]+rtn, pii(-1, -1));
priority_queue<pii> pq; // push the index where it came from not the original index
pq.push(pii(0, i));
for (int in: edges[i]) {
posses[in] = 0;
pq.push(pii(precomp[in][0].first+1, in));
}
for (int t = 0; !pq.empty() && t < rtn; t++) {
pii top = pq.top();
pq.pop();
int cnode = top.second;
if (top.first == -1) break;
if (cnode == i) {
precomp[i][t] = top;
break;
}
if (!vis[precomp[cnode][posses[cnode]].second]) {
precomp[i][t] = pii(top.first, precomp[cnode][posses[cnode]].second);
vis[precomp[cnode][posses[cnode]].second] = 1;
}
else {
t--;
}
posses[cnode]++;
if (posses[cnode] < rtn && precomp[cnode][posses[cnode]].first >= 0) pq.push(pii(precomp[cnode][posses[cnode]].first+1, cnode));
for (int t = 0; t < rtn; t++) if (precomp[i][t].second != -1) vis[precomp[i][t].second] = 0;
}
}
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(NULL);
cin >> n >> m >> q;
for (int i = 0; i < m; i++) {
int x, y; cin >> x >> y; x--; y--;
if (y < x) {
int temp = x; x = y; y = temp;
}
edges[y].push_back(x);
}
//rtn = max(1, (int) (sqrt(n)/15));
make();
for (int t = 0; t < q; t++) {
int pos, num;
cin >> pos >> num;
pos--;
if (num >= rtn) {
memset(inactive, 0, sizeof(bool)*n);
for (int i = 0; i < num; i++) {
int x; cin >> x; x--;
inactive[x] = 1;
}
for (int i = 0; i <= pos; i++) {
if (inactive[i]) {
dp[i] = -1;
}
else dp[i] = 0;
for (int in: edges[i]) {
if (dp[in] >= 0) dp[i] = max(dp[i], 1+dp[in]);
}
}
cout << dp[pos] << "\n";
continue;
}
vector<int> v;
for (int i = 0; i < num; i++) {
int x; cin >> x; x--;
vis[x] = 1;
v.push_back(x);
}
for (int i = 0; i < rtn; i++) {
if (!vis[precomp[pos][i].second]) {
cout << precomp[pos][i].first << "\n";
break;
}
}
for (int rv: v) vis[rv] = 0;
//assert(false);
}
}
