Let us try to divide the numbers by each option one by one.

Look at the last two digits of the numbers.

List all the numbers that can divide 24 and 72 both except 1.

Think of the multiples of 200 and 300.

Think about the common number in 7 and 9 times table.

Let us list all the factors first.

Think about the common number in 2 and 3 times table.

Which number out of the options, can divide all the three given numbers.

Think of the divisibility rule.

Which number out of the options, can divide all the three given numbers.