Which of the following is the best explanation for why the chromosome numbers above are all even? Diploid Chromosome Number
Fruit Fly 8
Human 46
Goldfish 94

1)

The diploid chromosome number represents two sets of chromosomes, one from each parent, so it is always an even number.

2)

Animal cells always have an even number of chromosomes, and plant cells always have an odd number of chromosomes.

3)

The number of chromosomes present in a diploid cell doubles for each generation because there are two parents.

i think its the first one

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."