Question

鼠的毛色类型由等位基因B、b控制，现有甲、乙黑毛雌鼠分别与褐毛雄鼠（丙）交配，甲三胎生出9只黑毛幼鼠和7只褐毛幼鼠；乙三胎生出19只黑毛幼鼠，则甲、乙、丙三只鼠的基因组成依次为

1. A.
   BB、Bb、bb                          
2. B.
   bb、Bb、BB
3. C.
   Bb、BB、bb                          
4. D.
   Bb、bb、BB

Answer 1

C