is/are more common in some families (indicating genetic influences), in some racial ethnic groups, and in women who use fertility drugs.

Dizygotic twin

Explanation:

Dizygotic twin is also known as fraternal twin, it occurs when two separate ova, or eggs, that are released at the same time from an ovary and are fertilized by separate sperm. Many women make use of fertility drugs, that facilitate or stimulate the production of ova, increasing the chance of multiple births. Dizygotic twins are more common in some families and also in some racial groups, because more women are having babies in their 30s, and that is the time when fertility start dropping in women.

hey, i believe your answer would be d. sugar ribose and the base uracil. i believe this is the answer, because rna consists of sugar ribose, adenine, guanine, cytosine, and uracil.

your first option is incorrect, because that's dna. where it consists of sugar deoxyribose, adenine, guanine, cytosine and thymine.

your second option is also incorrect, this is because sugar deoxyribose is in dna, and uracil is in rna. these two do not make sense together.

your third option being incorrect, because sugar ribose is in rna, but not the base of thymine. rna consists of uracil, not thymine.

lastly your fourth option being correct! this answer is correct, because both sugar ribose, and the base uracil are in rna! ~

answer is d. sugar ribose and the base uracil.