Question

the structure of dna is called the double helix. the word \double\ is used because
it is made up of two sugars = ribose & deoxyribose
it was discovered by two researchers--watson & crick
it has two sides = two sugar phosphate backbones
it has two pairs of matching bases = a with t & c with g

Explanation:

DNA's double - helix structure has two sugar - phosphate backbones, which is why the term "double" is used. DNA contains deoxyribose sugar, not ribose (which is in RNA). The discovery by Watson and Crick is not related to the "double" in double - helix. The base - pairing (A - T, C - G) is not the reason for the "double" in the structure name.

Answer:

it has TWO sides = two sugar phosphate backbones