Which of the following best describes what we mean by the universe? (A) all the galaxies in all the superclusters (B) the sum total of all matter and energy (C) a vast collection of stars that number as many as the grains of sand on all the beaches on Earth (D) our Milky Way Galaxy

(B) the sum total of all matter and energy

Explanation:

Universe comprises of all the matter and energy that exists in space. It contains billions of stars, planets and interstellar matter that is clouds of dust and gas. There is large amount of the empty space in between.

Universe contains stars as many as grains of sand on all beaches on the Earth. These stars are grouped into galaxies. Milky Way is one of the galaxies. Galaxies can be grouped into clusters and super-clusters.