How Does Carbon Fixation Differ Between C₃ and C₄ Plants

Multiple Choice

How does carbon fixation differ between C₃ and C₄ plants?

A) C₄ plants undergo carbon fixation by carboxylation of a four-carbon substrate (oxaloacetate) ,while in C₃ plants,a three-carbon compound (phosphoglycerate) is carboxylated.
B) Both C₃ and C₄ plants involve carboxylation of ribulose-1,5-bisphosphate by rubisco;but in C₃,the first stable intermediate is 3-phosphoglycerate,and in C₄,it is oxaloacetate.
C) C₃ plants don't undergo photorespiration,but C₄ plants do.
D) Rubisco is the primary enzyme that catalyzes carbon fixation in C₃ plants,and phosphoenolpyruvate carboxylase can catalyze carbon fixation in C₄ plants.