Which of the following is a prime number?

A. $153$

B. $142$

C. $135$

D. $196$

E. $127$ E. $127$

1. If the sum of each digit in three digit number is a multiple of $9$, then the number is a multiple of $9$. This is one of basic number theory that a number is divisible by $9$ if the sum of each digit number is a multiple of $9$. So, $153$ is not a prime number. 2. If the digit in one's place is either $0$ or $5$, then the number is a multiple of $5$. So, $135$ is not a prime number. 3. $142$ is a multiple of $2$ since it is an even number. So, it is not a prime number. A. $153$

B. $142$

C. $135$

D. $196$

E. $127$ E. $127$

$196$ is a square of a number. So, it is not a prime number.

Therefore, $127$ is a prime number.

*No More Steps*