Select the set in which the numbers are related in the same way as are the numbers of the given sets.

(NOTE : Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13 - Operations on 13 such as adding /subtracting /multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

(23, 25, 16)

(21, 17, 256)

(18, 15, 81)

(23, 25, 16)

(21, 17, 256)

The logic followed here is :

(Ist number  -   second number)⁴ = Third number

As

(23 - 25)⁴ = 16

(21 - 17)⁴ = 256

Same as in (18, 15, 81)

(18 - 15)⁴ = 81