Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: 
The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change.


Question: The number of neutrons and electrons may vary or change in an atom. what happens to the number of protons?
remains the same
The number of protons remains the same.