14 is related to 54 following a certain logic. Following the same logic, 9 is…

14 is related to 54 following a certain logic. Following the same logic, 9 is related to 24.

To which of the following is 21 related following the same logic?

(NOTE: Operations should be performed on the whole numbers, without breaking

down the numbers into their constituent digits. E.g. 13 – Operations on 13 such as

adding / subtracting /multiplying to 13 can be performed. Breaking down 13 into 1 and

3 and then performing mathematical operations on 1 and 3 is not allowed.)