hey, even though this sort of question is repetitive, this one contradicts my previous knowledge , can you please tell me where am I wrong ?
I narrowed the options down to three, as we can see the answer says offspring are 50% heterozygous , which means we can make sure that the white one is surely Cc and not cc
bc otherwise it would have been 100% ,additionally we can see that Cc is white , meaning dominant , so the other 50% offspring being Cc are white, but the answer says the only phenotype is black , what am I doing wrong ?
the answer is D
! Here is how I tried to attempt the question. First , the mouse 1 is homozygous dominant so it’s genotype is CC, breeding with a white mouse, the genotype of the white mouse must be cc. Their F1 generation line will all be black mouse with genotype Cc. Mating the mouse 1 CC and mouse 2 Cc we will get the F2 generation mice with genotype CC and Cc , all mice black with 50 percent of heterozygosity. Hope my explanation helps!
. I am referring to the genotype of the white mouse as “ cc” though. When I first read the question, I misread it and thought they want to ask the offsprings obtained from mating between a white mouse and a black mouse, but actually, the question is asking for the breeding between the mouse 1 and mouse 2 labeled in the picture. I think perhaps you were also thinking as the way I did 
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