I'm kinda confused. But surely if it was B (it is), then the grandparents will have genotype of Nn. If you cross them, it will be Nn * Nn, which will give offspring: NN, Nn, Nn, nn. But that's 3:1, but it shows 1:1 in the diagram.
Majorly confused.
Listen, listen Ivo you are majorly confused. Yes. See the ratios of male:female is always 1:1 but here you don't have it!!! It's different. It's just a matter of eliminating the wrong ones here. See C and D are definitely not correct. A can't be too either cause you won't have dominant individuals in that situation. So only B is left
. Just relax. Listen to Eminem lol and then start again
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