#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=2e6+10;
int a[N];

void solve()
{
    int n,k;
    cin>>n>>k;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
    }
    sort(a+1,a+n+1);
    queue<int> mmx,res;
    res.push(a[1]);
    int max_l=1;
    for(int i=2;i<=n;i++)
    {
        if(a[i]-res.front()<=k)
        {
            res.push(a[i]);
            if(res.size()>max_l)
            {
                max_l=res.size();
                //cout<<max_l<<endl;
            }
        }
        else
        {
            while(a[i]-res.front()>k&&!res.empty())
            {
                res.pop();
                //cout<<11111<<endl;
            }
            res.push(a[i]);
        }
    }
    cout<<max_l<<endl;
}
//1 3 5 6 8
signed main()
{
    int t;
    cin>>t;
    while(t--)
    {
        solve();
    }
    return 0;
}