How can blue-green be used to show depth in a sea scene?

Correct answer: Use lighter blue-green in distant water areas and darker blue-green in nearer water areas

The governing concept is atmospheric perspective supported by colour value. Distant areas usually appear lighter, softer, and less distinct because of the atmosphere, while nearer areas can show stronger, darker values. Therefore, lighter blue-green in the distance and darker blue-green in the foreground creates a convincing sense of depth, making option A correct. Option C reverses the usual value pattern, while B and D provide too little tonal variation to establish distance clearly.