The atomic number of a nucleus is the number of: a electrons b protons c neutrons d nucleons

B protons

Explanation:

- The atomic number of a nucleus (often labelled with Z) is the number of protons inside the nucleus

- The mass number of a nucleus (often labelled with A) is the sum of the protons and the neutrons inside the nucleus

- The number of electrons in a neutral atom is equal to the number of protons inside the nucleus

Therefore, the correct answer is

B protons

However, A (electrons) could also be considered correct if we are talking about a neutral atom.

33: i think it’s b