If m and n are integers divisible by 5, which of the following is not necessarily true ?

A. m + n is divisible by 10

B. m - n is divisible by 5

C. m² - n² is divisible by 25

D. None of these

Answer: Option A

Solution(By Examveda Team)

Take m = 15 and n = 20
Then, each one of m and n is divisible by 5
But (m + n) is not divisible by 10
Hence, (m + n) is divisible by 10 is not true.