A dihybrid cross AaBb × AaBb gives a phenotypic ratio of (with independent genes and complete dominance):
- A
1:2:1
- Bcheck_circle
9:3:3:1
- C
1:1:1:1
- D
3:1
Explanation
9 (A_B_) : 3 (A_bb) : 3 (aaB_) : 1 (aabb). Each parent produces 4 gamete types; their 4×4 = 16-box Punnett square shows the classic dihybrid result.