The original mice that you cross are called the parent generation. The offspring from that cross are called the first Filial generation.
answer:
if i were you i would copy the entire question into the search bar on brainly or on your regular seach engine
explanation:
it'll come up when you seach it on google or brainly
also quick tip instead of putting it as as image paste the question and the options and ask your question that way its clearer and other people can look up your question easily if they have the same one!
The answer is A as they both share the same cells