Natural selection is the process by which favorable traits are passed down through different generations of a species in order to adapt and likely survive within the changing environment.
Are there any kind of answer choices ?
Answer:
Mary Jean and Beth <u>volunteered</u> for the past five years at a local shelter for abused pets.
Explanation:
In the given sentence, the action/ verb is something that's done in the past. This is identified by the phrase "for the past five years", meaning it is an action that's been done in the past, that happened some years before the present. Therefore, the verb "volunteer" will be used on the past form "volunteered".
So, the newly revised sentence will become-
Mary Jean and Beth <u>volunteered</u> for the past five years at a local shelter for abused pets.