Question

which two parts make up the \backbone\ of dna?
nitrogenous bases
phosphate groups
deoxyribose sugar
rewatch
next question

Explanation:

The DNA backbone is composed of alternating deoxyribose sugar and phosphate groups, linked by phosphodiester bonds. Nitrogenous bases are attached to the sugar but are not part of the backbone.

Answer:

phosphate groups, deoxyribose sugar