Select the set in which the numbers are related in the same way as are the numbers of the following 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 /deleting /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)
(14, 28 , 84)
(17, 34, 102)

(14, 28 , 84)

(17, 34, 102)

Logic: First Number × 2 = Second Number and Second × 3 = Third Number.

​14 × 2 = 28

28 × 3 = 84

​17 × 2 = 34

34 × 3 = 102​​

Option A. (21, 42, 126)

21 × 2 = 42 

42 × 3 = 126 
Pattern matches

20 × 2 = 40 $$\not =$$​41

Doesn’t follow the pattern

20 × 2 = 40 $$\not=$$​ 41

Doesn’t follow

21 × 2 = 42 

42 × 3 = 126  $$\not=$$​ 136

Thus, the correct option is: (a) (21, 42, 126)​​