What Adaptation Allows C4 Plants to Minimize the Effects of Rubisco's

Multiple Choice

What adaptation allows C4 plants to minimize the effects of rubisco's inefficiency at high temperatures?  

A) C4 plants fix the carbon twice in two different types of cells.
B) C4 plants fix the carbon twice at two different times of day.
C) C4 plants fix the carbon only once.
D) C4 plants store products in vacuoles.
E) C4 plants only fix carbon at night.