Don’t base high school course selection on standardized testing.
SAT Subject Tests are recommended by very few schools. It’s theoretically mostly covered by standard HS Biology.
AP results are accepted for college placement by thousands of colleges. They are based on the approved content of an AP Bio HS course
So…what? Surely you don’t think you’ve covered everything/enough that you’ll ever need in first year HS Bio. Don’t be under the impression that a Bio Subject Test score will put you on equal footing to someone who has taken AP Bio.
If you’re looking for which class will be more attractive in a college admissions application, it would be AP Bio The best course for you depends on what you’re looking to pursue. Though the range that would point to Stats is very narrow.
As noted above, I’d recommend a language, history, computer science, or other course not on your schedule rather than doubling up on either as a Sophomore.