By far the most common elements in the Universe and in our Solar System are
A) nitrogen and oxygen.
B) iron and manganese.
C) hydrogen and helium.
D) hydrogen and oxygen.

Question

Quizplus · Accepted Answer

Hydrogen and helium are the most common elements in the Universe and in our Solar System, making up about 98% and 99% of their respective total masses. Nitrogen and oxygen are much less abundant, while iron and manganese are relatively rare. Therefore, the correct choice is C, hydrogen and helium.

By Far the Most Common Elements in the Universe and in Our