The most logical transition for the sentence is:
(Choice B) For example,
So the completed text would read:
"Many marine animals rely on sound, which travels faster and farther through water than through air, for critical functions like communication and navigation. For example, sperm whales use intricate sequences of clicks known as “codas” to identify one another, coordinate group movements, and locate prey during deep foraging dives."
This choice appropriately indicates that the following information is an example of the previous statement about marine animals using sound.