#include<bits/stdc++.h>
using namespace std;
namespace io
{
	constexpr int S1=1<<20;
	char buf1[S1],*l1,*r1;
	inline char getc()
	{
		return ((l1==r1&&(r1=(l1=buf1)+fread(buf1,1,S1,stdin)),l1!=r1)?*l1++:EOF);
	}
	template<typename T=int>inline T read()
	{
		T x=0,y=1;
		char c=getc();
		for(;c<'0'||c>'9';c=getc())
			if(c=='-')
				y=-1;
		for(;c>='0'&&c<='9';c=getc())
			x=c-'0'+x*10;
		return x*y;
	}
	constexpr int S2=1<<20;
	char buf2[S2],*l2=buf2;
	inline void putc(char c)
	{
		l2==buf2+S2&&(fwrite(buf2,1,S2,stdout),l2=buf2),*l2++=c;
	}
	int st[42];
	template<typename T>inline void write(T x,char end='\n')
	{
		if(x<0)
			putc('-'),x=-x;
		int tp=0;
		do
			st[++tp]=x%10;
		while(x/=10);
		while(tp)
			putc(st[tp--]+'0');
		if(end)
			putc(end);
	}
	inline void ps(const char*a,char end='\n')
	{
		for(const char*p=a;*p;p++)
			putc(*p);
		if(end)
			putc(end);
	}
	struct end
	{
		~end()
		{
			fwrite(buf2,1,l2-buf2,stdout);
		}
	}ender;
}
using io::getc;
using io::read;
using io::putc;
using io::write;
using io::ps;
constexpr long long mod=1000000007;
constexpr int MN=100005;
int n,m;
long long v;
pair<int,int>a[MN];
inline long long ksm(long long b,int p)
{
	long long res=1;
	for(;p;p>>=1)
	{
		if(p&1)
			res=res*b%mod;
		b=b*b%mod;
	}
	return res;
}
inline void work()
{
	n=read(),m=read(),v=read();
	for(int i=1;i<=m;i++)
		a[i].first=read(),a[i].second=read();
	sort(a+1,a+m+1);
	for(int i=1;i<m;i++)
		if(a[i].first==a[i+1].first&&a[i].second!=a[i+1].second)
		{
			puts("0");
			return;
		}
	long long ans=ksm(v,2*(a[1].first-1));
	for(int i=1;i<m;i++)
	{
		int k=a[i+1].first-a[i].first;
		if(!k)
			continue;
		long long t1=ksm(v,k-1),t2=t1*v%mod;
		ans=(t2*t2-t2+t1)%mod*ans%mod;
	}
	printf("%lld\n",(ans*ksm(v,2*(n-a[m].first))%mod+mod)%mod);
}
int main()
{
	freopen("assign.in","r",stdin);
	freopen("assign.out","w",stdout);
	int T=read();
	while(T--)
		work();
	return 0;
}