Which of the Following Statements Is(are) True

Which of the following statements is(are) true?
i.The number of protons is the same for all neutral atoms of an element.II.The number of electrons is the same for all neutral atoms of an element.III.The number of neutrons is the same for all neutral atoms of an element.

A) I, II, and III are all true.
B) I, II, and III are all false.
C) Only I and II are true.
D) Only I and III are true.
E) Only II and III are true.