01 How may a white wall appear under yellow light?
Answer and explanation
Correct answer: A. Relatively warm
Explanation: The governing concept is reflected-light colour perception. A white wall reflects much of the light falling on it, so under yellow or warm illumination it can acquire a yellowish, warmer appearance even though its material has not changed. It will not normally become black, and yellow light does not inherently make it blue or green. Therefore, the relative warm appearance in option A is correct.