A student says that yellow is always a primary colour. What is the best evaluation?

Correct answer: The statement depends on the system; yellow is secondary in light

The governing concept is that primary and secondary labels depend on the colour system. In traditional RYB pigment teaching, yellow is treated as a primary colour. In additive RGB light, however, red and green combine to make yellow, so yellow is secondary there. Option A is therefore the best evaluation; the other choices make an unjustified universal claim or deny a basic colour.