Four particles are represented by the symbols: $^{{40}}_{{20}}W$, $^{{41}}_{{20}}X^{{2+}}$, $^{{37}}_{{18}}Y$, $^{{37}}_{{17}}Z$. The letters are not the chemical symbols. Which of the particles contain the same number of neutrons?
- AW and $X^{2+}$
- BW and Z
- C$X^{2+}$ and Y
- DY and Z