Which of the following would result in fraternal twins

Which of the following would result in fraternal twins, who don't have identical DNA? A. Two sperm fertilizing a single egg B. One sperm fertilizing a single egg C. Two sperm fertilizing two different eggs that were released in the same cycle D. One sperm fertilizing a single egg that splits into two embryos

Fraternal twins do develop when two sperms do fertilize two different ova that are released at the same time of a menstrual cycle.

Option C

Twins are of two types - Monozygotic twins or identical twins, and Dizygotic twins or fraternal twins.

Fraternal twins develop rarely, when during the menstrual cycle of the would be mother, two ova are released by two ovaries. So, two sperms fertilize the two ova separately. These zygotes develop into two separate embryo in their own separate amniotic sac. Being developed from separate sperm and separate ovum, the twins have not much similar characteristics unlike identical twins.

Only the fraternal twins can have different genders, like one can be male and other female. Monozygotic twins are always of same gender.

"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."