The mean photosynthetic rates of\[{{C}_{3}}\]and\[{{C}_{4}}\]plants per\[d{{m}^{2}}\]per hour are respectively

• A. 10 mg and 20 mg
• B. 90 mg and 22 mg
• C. 22 mg and 75 mg
• D. 75 mg and 22 mg