I believe the correct answer is C, but I'm 100% on this. Hope this helped though!
-TTL
Answer:
The proton gradient produced by proton pumping during the electron transport chain is used to synthesize ATP. Protons flow down their concentration gradient into the matrix through the membrane protein ATP synthase, causing it to spin (like a water wheel) and catalyze conversion of ADP to ATP.
A) It becomes a negative ion
I'm only a seventh grader, but I say b. tell me if I'm right plz.
