Which practice is correct for making an even, clean orange?

Correct answer: Mix red and yellow thoroughly

In traditional subtractive art colour mixing, orange is a secondary colour made from the primary colours red and yellow. Mixing these two paints thoroughly and in a controlled proportion distributes the pigments evenly and produces a cleaner orange, so option A is correct. Blue and green do not make orange, while mixing all three primary colours often produces a dull, muddy result. Water alone adds no orange pigment.