Question

complete the text with the better adverbial conjunction.
scientists in a remote region of russia have been restoring a prehistoric ecosystem hospitable to extinct animals like the woolly mammoth. ____, if scientists are ever successful in resurrecting the woolly mammoth, it will need a place to roam.
after all
in short

Explanation:

"After all" is used to introduce a reason or explanation that supports a previous statement. In this case, the first sentence says scientists are restoring a prehistoric ecosystem. The second sentence explains why (because if they resurrect the mammoth, it needs a place to roam). "In short" is used to summarize, which is not the case here.

Answer:

After all