Why Does an Electrochemical Potential Build Up in Mitochondria, but Not

Multiple Choice

Why does an electrochemical potential build up in mitochondria, but not in chloroplasts?

A) Proton movement into the thylakoid lumen is neutralized by the movement of other ions.
B) Proton movement into the intercristal space is neutralized by the movement of other ions.
C) Proton movement into the cristae lumen is neutralized by the movement of other ions.
D) The protons in chloroplasts are immediately joined to electrons.
E) The protons in mitochondria are immediately joined to electrons.