Question

the atomic number of oxygen, 8, indicates that there are eight

protons in the nucleus of an oxygen atom

oxygen nuclides

neutrons outside the oxygen atoms nucleus

energy levels in the oxygen atoms nucleus

Explanation:

The atomic number of an element is equal to the number of protons in the nucleus of its atom. For oxygen with an atomic number of 8, it means there are 8 protons in the nucleus of an oxygen atom. Oxygen nuclides refer to different isotopes of oxygen, neutrons are in the nucleus not outside, and energy - levels are not related to the atomic number in this context.

Answer:

protons in the nucleus of an oxygen atom