Which substance's presence makes urine light yellow?

Think it through first, then pick an option.

Answer and explanation

Correct answer: a Urochrome

The pigment urochrome makes urine light yellow.

Why the other options are wrong

b Creatinine: Creatinine is a waste, not a pigment; a rise in blood suggests kidney failure.
c Urea: Urea is a nitrogenous waste and is not responsible for the colour.
d Uric acid: Uric acid is a waste; it does not give urine its yellow colour.