According to the 3 domain system of classification with the 3 domains being, Archaea, Bacteria and Eukarya, which of the following would be LEAST likely to belong to the domain Bacteria:

W) chlamydia

X) spirochetes (read as: spy-row-keets)

Y) gram positive bacteria

Z) non-nucleated thermophiles
Z) NON-NUCLEATED THERMOPHILES