In Mendel s experiments on garden pea plants, he performed a dihybrid cross of round yellow and green wrinkled seed plants. In the F2 generation, he sampled 1600 plants. Which of the following represents the correct number of plants of each phenotype?

• A. 900 round yellow, 300 round green, 300 wrinkled yellow and 100 wrinkled green
• B. 900 round green, 300 round yellow, 300 wrinkled yellow and 100 wrinkled green
• C. 900 wrinkled green, 300 round yellow, 300 wrinkled yellow and 100 round green
• D. 900 round green, 300 wrinkled green, 300 wrinkled yellow and 100 round yellow