In one mouse species, fur colour may be either black or white. Two black female mice were each allowed to mate with the same black male. One female produced nine offspring, all of them black. The other female produced seven offspring, five black and two white. One of the white mice was male, and is allowed to mate with a heterozygous female. What phenotypic ratio is expected in their offspring?
- A1 black : 1 white
- B1 black : 3 white
- C1 black : 2 grey : 1 white
- D3 black : 1 white