Answer: Option 'C' is correct.
Explanation:
Since we have given that
Number of painters to paint the interior of a house = 2
According to question, amount of time it takes to paint the house is inversely related to the number of painters.
So, Time is inversely related to number of painters.
If the number of painters to paint the house = 6
So, we get

Hence, it will take 4 hours to paint the house by 6 painters.
Therefore, Option 'C' is correct.