I dunno ♀️ sorryyyyyyyyyy
Answer:
a. hydroxyle in tyrosine
b. 3' OH
Request: Please mark me as the Brainliest.
Answer: The literal reason would be because our ancestors did. The ancestors of all modern mammals had five digits on each limb up to 360 million years ago.
Explanation:
The answer is A, bacteria can move around, use energy, and reproduce just like humans can, the only difference is they're single cell and we're not.