Which of the following best describes an isotope Which of th

Which of the following best describes an isotope?

an atomic structural variation in which atoms have differing numbers of protons

an atomic structural variation in which atoms have valence shell difference

an atomic structural variation in which atoms have differing numbers of electrons

an atomic structural variation in which atoms have differing numbers of neutrons

Isotopes have the same number of protons (and electrons), but different numbers of neutrons.

So Answer is an atomic structural variance in which atoms have differing number of neutrons