Select the set in which number are related in the same was as are the numbers of the following sets.
(NOTE: Operation should be performed on the whole numbers, without breaking down the numbers into its constituents digits. E.g 13- Operations on 13 such as adding / subtracting, multiplying et(c) to 13 can be performe(d) Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 are not allowed.

(36, 78, 13)

(121, 77, 7)

Correct option is A

Given: 

Set I - (36, 78, 13) → $$\sqrt{36} \times 13 = 6 \times 13 = 78$$​​

Set II - (121, 77, 7) → $$\sqrt{121} \times 7 = 11 \times 7 = 77$$​​

Logic: $$\sqrt{1st} \times 3rd = 2nd$$  

From the given options 

(a) ​(49, 63, 9) → $$\sqrt{49} \times 9 = 7 \times 9 = 63 = 63$$​​

(b) ​(36, 72, 10) → ​$$\sqrt{36} \times 10 = 6 \times 10 = 60 \not= 72$$​​

(c) (9.56, 18) → $$\sqrt{9} \times 18 = 9 \times 18 = 162 \not= 56$$​​

(d) ​(64, 85, 12) → $$\sqrt{64} \times 12 = 8 \times 12 = 96 \not= 85$$​​

Correct answer is (a)