What is the most likely result of adding a small amount of red to yellow?

Correct answer: Yellow-orange

The governing concept is an intermediate colour produced by neighbouring hues. Yellow mixed with a small amount of red shifts slightly toward orange, so the resulting colour is yellow-orange and option B is correct. Because yellow remains the dominant colour, the mixture does not become full orange immediately. Green would require blue, blue-violet would require blue and red, and grey is not the expected result of this warm-colour mixture.