Which choice best matches the meaning of the underlined word as it is used in the paragraph?

while driving through wyoming, we could not locate a motel. it got later and later and we were exhausted. when we finally saw a vacancy sign glimmering in the distance, we were so ! the place wasn't fancy, but at least it was clean and we had a good night's sleep.

a.
welcome

b.
clean and safe

c.
motel

d.
empty or not filled

underlined word is vacancy