def max_len(arr, k):
	events = {}
	
	for x in arr:
		l = x-k
		r = x+k
		
		events[l] = events.get(l, 0)+1
		events[r+1] = events.get(r+1,0) -1
		
	current = 0
	ans = 0
		
	for x in sorted(events):
		current += events[x]
		ans = max(ans, current)
	return ans
		
t = int(input())

for _ in range(t):
    n, k = map(int, input().split())
    a = list(map(int, input().split()))

    print(max_len(a, k))