#include <bits/stdc++.h>
using namespace std;
const int M = 100005;
const int Mod = 1000000007;
int n,m,v;//1 <= n <= 1e9 1 <= m <= 1e5 2 <= v <= 1e9
struct Node{
	int c,d;
}a[M];
bool cmp(Node a,Node b)
{
	if (a.c < b.c) return 1;
	return 0;
}
map<int,int> mp;
long long quik(int num)
{
	//cout << num << endl;
	long long ans = 1;
	for (int i = 0; num > 0; i++)
	{
		if ((num & (1 << i))) 
		{
			ans *= mp[(1 << i)];
			//printf("mp[%d]=%d\n",(1<<i),mp[1<<i]);
			ans %= Mod;
			num -= (1 << i);//cout << num << endl;
		}
	}
	//if (ans == 0) cout << "ddfdf" << endl;
	return ans;
}
int main ()
{
	//freopen("assign2.in","r",stdin);
	int T;
	scanf("%d",&T);
	while (T--)
	{
	    memset(a,0,sizeof a);
		scanf("%d%d%d",&n,&m,&v);
		//exit(0);
		for (int i = 1; i <= m; i++) scanf("%d%d",&a[i].c,&a[i].d);
		sort(a + 1,a + 1 + m,cmp);
		for (int i = 0; (1ll << i) <= 2 * n; i++)
		{
			if (i == 0) mp[(1 << i)] = v;
			else
			{
				mp[(1 << i)] = (1ll*mp[1 << (i - 1)] * mp[1 << (i - 1)]) % Mod;
				//printf("mp[%d]=%d\n",(1<<i),mp[1<<i]);
			}
		}
		//cout << endl << endl;
		long long ans = quik(2 * (a[1].c - 1));
		//cout << ans << endl;
		for (int i = 1; i <= m; i++)
		{
			while (i + 1 <= m && a[i].c == a[i + 1].c)
			{
				if (a[i].d != a[i + 1].d)
				{
					ans = 0;
					break;
				}
				i++;
			}
			if (ans == 0) break;
			
			if (i + 1 <= m)
			{
				ans *= quik(2 * (a[i + 1].c - a[i].c)) - quik(a[i + 1].c - a[i].c) + quik(a[i + 1].c - a[i].c - 1);
				ans %= Mod;
			}
			else
			{
				ans *= quik(2*(n - a[i].c));
				ans %= Mod;
			}
		}
		printf("%lld\n",ans);
		//exit(0);
	}
	return 0;
}