Answer:
Animals are made up of eukaryotic cells, meaning they have a nucleus which contains the DNA. :)
Answer:
As the generations are increasing or gets much over time, we have a more likelihood of seeing a response to natural selections as the favourable alleles are going to be moved from one generation to the next while those that are not favourable would be eliminated over generations.
If the new host gives allowance for early reproduction and ease of access then the generations each year would rise.
Not sure but my best guess is to go with B. It just makes the most sense.