The answer is A. Air
because our sound travel in the air so bat`s waves should travel in the air to find the insects that are flying in the air! :)))
i hope this is helpful
have a nice day
Organ. An organ is a system of tissues that work together on a larger scale to do certain jobs within an animal's body. Examples of organs are the brain, heart and lungs. Anatomy is an example of a biology specialty concerned with this level.
