Select the option that is related to the third number in the same way as the second number is related to the first number and the sixth number is related to the fifth number.

13 : 4 : : 19 : ? : : 16 : 5

6

13 : 4 : : 19 : ? : : 16 : 5

The logic followed here is:

IInd number × 3 + 1 = Ist number

As

13 : 4

4 × 3 + 1 = 13

16 : 5

5 × 3 + 1 = 16

Similarly

19 : ?

X × 3 + 1 = 19

3X = 19 - 1

3X = 18

X = 6