Answer
B.
Work Step by Step
In order to find the prime factorization of 40, we can try to divide 40 by the first prime, 2.
$40\div2=20$
Try to divide 20 by 2.
$20\div2=10$
Try to divide 10 by 2.
$10\div2=5$
5 itself is a prime number, so we cannot simplify any more. The prime factorization of 40 is $2\times2\times2\times5=2^{3}\times5$.
