Final answer:
Countershading is when a creature's dorsal surface is darkly colored and its ventral surface is silvery white. This makes it hard to be seen from above or below.
Step-by-step explanation:
The correct answer is A. Countershading. Countershading is a type of camouflage where an animal's dorsal surface is darkly colored and its ventral surface is lighter or silvery white. This coloration helps the animal blend in with its surroundings, making it harder to be seen from above or below.
For example, sharks have a dark-colored back and a lighter-colored belly, which helps them blend in with the ocean when seen from above or below.