Which colour is obtained by mixing red and blue?

Correct answer: Violet

According to the traditional painting colour wheel, red and blue are primary colours, and mixing them produces violet, a secondary colour. Thus, option D is correct. The other pairings help rule out the distractors: yellow and blue produce green, while red and yellow produce orange. Yellow is itself a primary colour, so it is not the expected result of mixing red with blue in this school-level model.