Which colour may form between red and blue if they are blended directly in a sunset?

Correct answer: Purple

The governing concept is the result of mixing neighbouring paint colours in a transition. Red and blue pigments can produce a purple or violet mixture, especially when they meet directly without an intermediate warm colour. Therefore option D is correct. Green requires blue and yellow, orange is commonly made from red and yellow, and yellow cannot result from directly combining red with blue. The precise purple depends on pigment bias and proportions.