#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b) {
    int x = 1;
    a %= M;
    while (b) {
        if (b & 1) x = (x * a) % M; 
        a = (a * a) % M;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************

vector<int> a;

int modInverse(int n){
    return power(n, M-2);
}

int consistency(int n, int m){
    
    unordered_map<int,int> freq;
    vector<int> b;

    for(int i=0; i<n; i++){
        if(!freq.count(a[i])){
            b.push_back(a[i]);
        }
        freq[a[i]]++;
    }

    sort(begin(b), end(b));
    n = b.size();
    

    int freqM = 1;
    int ans = 0;

    int s = 0, e = 0;
    while(e<n){

        freqM = (freqM * freq[b[e]])%M;

        if(e-s+1 < m){
            e++;
        }
        else{

            while(s<=e && b[e]-b[s] >= m){
                freqM = (freqM * modInverse(freq[b[s]])) % M;
                s++;
            }

            if(e-s+1 == m){
                ans = (ans + freqM)%M;
            }
            e++;
        }
    }


    return ans;    
}















int practice(int n, int m){


    return 0;
}





void solve() {
    
    int n, m;
    cin>> n >> m;
    
    a.resize(n);
    for(int i=0; i<n; i++) cin >> a[i];
    
    cout << consistency(n, m) << endl;


}





int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}