Radio waves are visible. Radio waves have a high frequency. Radio waves spread in all directions. Radio waves are created by the animal.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Collars that emit radio waves are sometimes placed on animals to find their location. Which is the best reason for using radio waves as a method of tracking the animals?
Possibilities:
- Radio waves are visible.
- Radio waves have a high frequency.
- Radio waves spread in all directions.
- Radio waves are created by the animal.

Radio waves spread in all directions.