An astrophysicist studying stellar nucleosynthesis in a supernova remnant analyzes four ionic and atomic species, WWW, XXX, YYY, and ZZZ. Their subatomic compositions are recorded in the table below.
SpeciesNumber of protonsNumber of neutronsNumber of electronsW161818X161816Y162016Z182218 \begin{array}{c|c|c|c} \text{Species} & \text{Number of protons} & \text{Number of neutrons} & \text{Number of electrons} \\ \hline \text{W} & 16 & 18 & 18 \\ \text{X} & 16 & 18 & 16 \\ \text{Y} & 16 & 20 & 16 \\ \text{Z} & 18 & 22 & 18 \\ \end{array} SpeciesWXYZNumber of protons16161618Number of neutrons18182022Number of electrons18161618Which two species are neutral isotopes of the same element?
WWW and XXX
WWW and YYY
XXX and YYY
YYY and ZZZ