What is generally produced by mixing yellow and violet?

Correct answer: Muted brown or grey

The governing concept is the neutralising effect of complementary pigments. Yellow and violet are complementary colours because they are opposite on the traditional colour wheel. When mixed as paint, their combined pigments absorb more portions of visible light, lowering saturation and brightness and generally creating a muted brown, grey, or grey-brown colour. Thus option D is correct; the bright orange, light blue, and pure green choices are not expected outcomes.