1. Which of the following statements is (are) true?
I. O and F have the same number of neutrons.
II. C and N are isotopes of each other because their mass numbers are the same.
III. O
2– has the same number of electrons as Ne.
(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I and III only

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