Explanation:

- Let's examine the relationship:

- The pair is 39 : 27.

- 39 – 12 = 27, so the relationship is subtracting 12.

- The question: 43 : ?

- To keep the pattern, subtract 12 from 43: 43 – 12 = 31.

- Let's check the provided options:

- Option 1: 12

- Option 2: 6

- Option 3: 38

- Option 4: 20

- None of the options is 31.

- Let's see if there is another pattern. Odd numbers? Cubes?

- 39 and 27: 27 (3³), 39 is not a cube.

- 43 and the answer? None fits with simple cubes or squares.

- Maybe difference of 12 is the closest basic pattern.

- But according to the question and options, none match the logic exactly.

- However, based on 39 – 27 = 12, one might consider option 1 (12), thinking the answer refers to the difference.

- However, the question format asks for the number related to 43, not the difference.

- So, none of the provided options fit the correct pattern.