Option A) 18 is correct
$1440=2^5*3^2*5^1$
No of factors of $1440$= $(5+1)(2+1)(1+1)$=$36$
1440 is not a perfect square so no of ways it can be written as product of two factors = $36/2=18$
If n is not a perfect square then no of ways it can be written as product of factors= (# of factors of n)/2
If n is a perfect square then no of ways it can be written as product of factors = (# of factors of n -1)/2