Is it more likely that the single whale in question truly is alone, or is its call simply a manifestation of sound waves in the ocean?

For decades a single whale has called at a frequency no other whale answers, and no one can say whether it is truly alone or simply speaking a language the rest of the ocean cannot hear.

• Option 1: It's highly likely that the whale is truly alone
• Option 2: The whale's call is just an echo in the ocean