The composition of matter in the universe can be summarized by which statement?
A) All but 2% of the mass of the universe is hydrogen and helium.
B) All but 2% of the mass of the universe is hydrogen.
C) Two percent of the mass of the universe is hydrogen and helium; the rest is of heavier elements.
D) About half of the mass of the universe is in the form of rocks, molecules, and planetary material.

Question

Quizplus · Accepted Answer

The universe is primarily composed of hydrogen and helium, making up about 98% of its mass, with heavier elements constituting the remaining 2%.

The Composition of Matter in the Universe Can Be Summarized