Which of the following is composed of a collection of planets, their moons, and other objects orbiting a centeral star?

A solar system is your answer. You didn't give any options, but that is the answer.

Definition of solar system: the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets.

That's how I figured it out :)

well

explanation:

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.