#include<bits/stdc++.h>
#define Int int
#define pb emplace_back
#define mkp std::make_pair
#define pll std::pair<ll,ll>
typedef long long ll;
const int M = 1e5 + 10;
const ll mod = 1e9 + 7;
int read() {
	int x = 0, f = 1;
	char c = getchar();
	while(c < '0' || c > '9') {
		if(c == '-') f = -1;
		c = getchar();
	}
	while(c >= '0' && c <= '9') {
		x = (x << 1) + (x << 3) + (c ^ 48);
		c = getchar();
	}
	return x * f; 
}

int m;
ll n, v;
pll c[M];

ll qpow(ll a, ll b) {
	if(b < 0) return 1;
	ll res = 1;
	for(; b; b >>= 1, a = a * a % mod) if(b & 1) res = res * a % mod;
	return res;
}

int main() {
	freopen("assign.in", "r", stdin);
	freopen("assign.out", "w", stdout);
	int T = read();
	while(T--) {
		n = read(), m = read(), v = read();
		for(int i = 1;i <= m; i++) c[i].first = read(), c[i].second = read();
//		if(T > 7) continue;
		std::sort(c + 1, c + m + 1);
		ll ans = 1;
		ans *= qpow(v, 2 * c[1].first - 2);
		ans %= mod;
		for(int i = 1; i < m; i++) {
			if(c[i].first == c[i + 1].first && c[i].second != c[i + 1].second) {
				ans = 0;
				break;
			}
			if(c[i].first == c[i + 1].first) continue;
			if(c[i].first == c[i + 1].first - 1) {
				ans *= (v * v - v + 1) % mod;
				ans %= mod;
			} else {
				ll l = c[i + 1].first - c[i].first - 1;
				ans *= ((v * v - v + 1) % mod * qpow(v, l) % mod + qpow(v, l + 2) * (qpow(v, l) - 1) % mod) % mod;
				ans %= mod;
			}
		}
		ans *= qpow(v, 2 * (n - c[m].first));
		ans %= mod;
		std::cout << ans << '\n';
	}
	return 0;
}