#include <bits/stdc++.h>
#define fi first
#define se second
#define FOR(i, a, b) for (int i = a, _b = b; i <= _b; ++i)
#define FORD(i, a, b) for (int i = a, _b = b; i >= _b; --i)
#define FORLL(i, a, b) for (ll i = a, _b = b; i <= _b; ++i)
#define FORDLL(i, a, b) for (ll i = a, _b = b; i >= _b; --i)
#define all(x) x.begin(), x.end()
#define uni(x) sort(all(x)), x.erase(unique(all(x)), x.end())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__)
template<typename T>
void __prine_one(const char *&s, const T &x)
{
while (*s == ' ') ++s;
const char *p = s;
int bal = 0;
while (*s)
{
if (*s == '(') ++bal;
else if (*s == ')') --bal;
else if (*s == ',' && bal == 0) break;
++s;
}
cerr.write(p, s - p) << " = " << x;
if (*s == ',')
{
cerr << " , ";
++s;
}
}
template<typename... Args>
void debug(const char *s, Args... args)
{
cerr << "[ ";
int dummy[] = {0, (__prine_one(s, args), 0)...};
(void)dummy;
cerr << " ]\n\n";
}
template<class X, class Y>
bool maximize(const X &a, const X &b)
{
if (a < b)
{
a = b;
return true;
}
return false;
}
template<class X, class Y>
bool minimize(const X &a, const X &b)
{
if (a > b)
{
a = b;
return true;
}
return false;
}
// --------------------------------------------------------------------------------------------
const int maxn = 1e5 + 3, B = 201;
int n, m, q;
vector<int> g[maxn], rg[maxn];
// --------------------------------------------------------------------------------------------
namespace AC
{
bool vis[maxn];
vector<pii> dp[maxn];
int DP[maxn];
vector<int> topo;
void dfs_topo(int u)
{
vis[u] = 1;
for (int v : g[u])
if (!vis[v]) dfs_topo(v);
topo.push_back(u);
}
void solve()
{
FOR(i, 1, n)
{
if (vis[i]) continue;
dfs_topo(i);
}
reverse(all(topo));
FOR(i, 1, n)
vis[i] = 0;
for (int u : topo)
{
vector<int> used;
priority_queue<pair<pii, pii>> pq;
FOR(i, 0, (int)rg[u].size() - 1)
{
int v = rg[u][i];
if (dp[v].empty()) continue;
pq.push({dp[v][0], {v, 0}});
}
int CNT = B;
while (CNT && pq.size())
{
auto Top = pq.top(); pq.pop();
if (!vis[Top.fi.se])
{
--CNT;
vis[Top.fi.se] = 1;
used.push_back(Top.fi.se);
dp[u].push_back({Top.fi.fi + 1, Top.fi.se});
}
auto nxt = Top.se;
if (nxt.se < dp[nxt.fi].size() - 1)
{
pq.push({dp[nxt.fi][nxt.se + 1], {nxt.fi, nxt.se + 1}});
}
}
if (dp[u].size() < B)
dp[u].push_back({0, u});
for (int v : used)
vis[v] = 0;
}
FOR(i, 1, n)
vis[i] = 0;
while (q--)
{
int src, k; cin >> src >> k;
vector<int> vec;
FOR(i, 1, k)
{
int x; cin >> x;
vec.push_back(x);
vis[x] = 1;
}
if (k < B)
{
// cerr << "TYPE1\n";
int res = -1;
for (auto &p : dp[src])
{
// dbg(p.se);
if (!vis[p.se])
{
res = max(res, p.fi);
break;
}
}
cout << res << '\n';
}
else
{
// cerr << "TYPE2\n";
FOR(i, 1, n)
{
DP[i] = vis[i] ? -1 : 0;
}
for (int u : topo)
{
if (DP[u] == -1)
continue;
if (u == src) break;
for (int v : g[u])
{
DP[v] = max(DP[v], DP[u] + 1);
}
}
cout << DP[src] << '\n';
}
for (int x : vec)
vis[x] = 0;
}
}
}
void solve()
{
cin >> n >> m >> q;
FOR(i, 1, m)
{
int u, v; cin >> u >> v;
g[u].push_back(v);
rg[v].push_back(u);
}
AC :: solve();
}
signed main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define TASK "TEST"
if (fopen(TASK".INP", "r"))
{
freopen(TASK".INP", "r", stdin);
freopen(TASK".OUT", "w", stdout);
}
solve();
return 0;
}
