Which pigment choice is more suitable for making a bright green in watercolour?

Correct answer: A green-biased blue and a blue-biased yellow

The governing concept is subtractive pigment mixing and colour bias. To mix a bright green, choose a blue that leans toward green and a yellow that leans toward green; these pigments share the desired direction and introduce less unwanted red or orange influence. Therefore, option A is correct. Red-biased blue and orange-biased yellow tend to neutralise the mixture, while blue-red and yellow-violet pairs produce different or duller results.