The following options apply regarding the effects of efforts to protect biodiversity on gray whales:
- Their numbers have increased because of the Endangered Species Act.
- They are an example of protecting biodiversity through the passage of laws.
The other options are not accurate in the context of gray whales:
- They are currently endangered and almost extinct. (Gray whales are not currently considered endangered; they have seen population recovery.)
- Their numbers have increased mostly due to captive breeding. (Gray whales have not been significantly impacted by captive breeding, as they typically do not breed well in captivity.)
- They are still being hunted, and their numbers are declining. (While some whaling still occurs, the overall population has increased and is not in decline.)