Question

which type of bond is represented by a hydrogen bond, which holds nitrogen bases together? a. b. c.

Explanation:

The question asks about the bond that holds nitrogen bases together in a DNA structure. Hydrogen bonds are the type of bond that pair nitrogenous bases (e.g., adenine - thymine, cytosine - guanine) in DNA. Looking at the options, option A shows a structure that likely represents the pairing of nitrogen bases (as in a DNA ladder - like structure where the 'rungs' are base - pairs held by hydrogen bonds). Option B seems to represent a phosphate group (a component of the DNA backbone, not the bond between bases), and option C likely represents a sugar (deoxyribose, also part of the DNA backbone).

Answer:

A.