Which model(s) demonstrate(s) how genetic diversity can occur during meiosis? Question 9 options:

Model B only because it is showing crossing over, which is the primary way genetic variation occurs during meiosis.

Both model A and B. Model A shows nondisjunction, which is an error during meiosis that causes genetic variation. Model B shows crossing over, which occurs regularly during meiosis and causes genetic variation.

Model A only because it is showing nondisjunction, which is the primary way genetic variation occurs during meiosis.

Both model A and B. Model A shows crossing over, which is an error during meiosis that causes genetic variation. Model B shows nondisjunction, which occurs regularly during meiosis and causes genetic variation

Both model A and B. Model A shows nondisjunction, which is an error during meiosis that causes genetic variation. Model B shows crossing over, which occurs regularly during meiosis and causes genetic variation.

Explanation:

TRust me!  i knoww it

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

"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."