#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
vector<pair<int, int>> st;
#define MAX 303030
#define MOD 1'000'000'007
vector<int> adj[MAX];
int dep[MAX];
int vis[MAX];
vector<int> ds;
void dfs(int x, int p = 0) {
	vis[x] = 1;
	for (auto v : adj[x]) {
		if (p == v) continue;
		if (vis[v]) {
			if (dep[x] < dep[v]) ds.push_back(dep[v] - dep[x] + 1);
			continue;
		}
		dep[v] = dep[x] + 1;
		dfs(v, x);
	}
}
ll dp[MAX];
ll mp[MAX];
ll mpow(ll x, ll y = MOD - 2) {
	ll ans = 1;
	ll mul = x;
	int i;
	for (i = 0; i <= 62; i++) {
		if (y >> i & 1) ans = (ans * mul) % MOD;
		mul = (mul * mul) % MOD;
	}
	return ans;
}
void solve() {
	int N, M;
	ll K;
	cin >> N >> M >> K;
	int i, a, b;
	for (i = 1; i <= N; i++) adj[i].clear(), dep[i] = vis[i] = 0;
	for (i = 1; i <= M; i++) {
		cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	dfs(1);
	dp[1] = K;
	dp[2] = K * (K - 1);
	dp[2] %= MOD;
	mp[0] = 1;
	for (i = 1; i <= N; i++) {
		mp[i] = mp[i - 1] * (K - 1);
		mp[i] %= MOD;
	}
	for (i = 3; i <= N; i++) {
		dp[i] = K * mp[i - 1] + (MOD - dp[i - 1]);
		dp[i] %= MOD;
	}
	ll fac = (K - 1) * mpow(K);
	fac %= MOD;
	int sum = N;
	ll ans = 1;
	for (auto v : ds) {
		ans = (ans * dp[v]) % MOD;
		sum -= v;
	}
	ans *= mpow(K, sum);
	ans %= MOD;

	sum += ds.size();
	ans *= mpow(fac, sum - 1);
	ans %= MOD;
	cout << ans << '\n';
}
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	int T;
	cin >> T;
	while (T--) solve();
}