Which one of the following is true about C₄ plants?

• A. They minimize rubisco oxygenase activity by fixing CO₂ into oxaloacetate
• B. They mainly occur in areas of high temperature and light intensity
• C. They minimize the rubisco oxygenase activity by fixing CO₂ into phosphoenolpyruvic acid
• D. C₃ plants are more efficient in photosynthesis than C₄ plants