What visual effect is generally produced by applying a transparent yellow layer over a dry blue layer?

Correct answer: Green

In transparent watercolour glazing, the upper yellow layer visually combines with the blue layer beneath it. Since blue and yellow are commonly understood as primary colours that produce green when mixed, the transparent overlap generally appears green, making option B correct. Violet requires blue with red, orange requires yellow with red, and red is not the expected result of this pair.