Final answer:
The sugars in DNA bind to the nitrogenous bases at the 1' carbon and the phosphate groups at the 5' carbon. Nucleosides are the combination of a sugar and a base without the phosphate group, and deoxyribonucleosides are nucleosides that contain the sugar deoxyribose.
Step-by-step explanation:
The ribose/deoxyribose sugars in DNA bind to the nitrogenous bases at the 1' carbon, and the phosphate groups at the 5' carbon of purines and pyrimidines respectively. A nucleoside consists of a nitrogenous base bonded to a pentose sugar (ribose or deoxyribose) without the phosphate group. A deoxyribonucleoside is a nucleoside that includes the sugar deoxyribose, which is the sugar present in DNA.
The correct answer to the student's question is A) 1st carbon, 5th carbon, because the nitrogenous base is attached to the 1' carbon of the sugar, and the phosphate group is attached to the 5' carbon of the sugar.