sabineodf wrote:

Unsure how A is sufficient (I know that's the answer but I'm hoping someone could help show me why)

For me A is insufficient because:

if n= k(k+1)(k-1)

we can get several cases, such as

k= 0

0*1*(-1) = -1 <-- not divisible by 6

k=1

1*2*0 = 0 <-- not divisible by 6

k=2

2*3*1 = 6 <--- divisible by 6

And so on. Statement 2 could supplement to my dilemma here, but since the answer is A, does anyone have a dumbed down explanation?

k cannot be 0 as k is a positive integer. And, k cannot be 1 as n is also a positive integer. Hence, k can only be >=2.