Finish the enthusiastic travel agent's email to a client.

We can book the mountain cabin or the beach house. ___ option sounds fantastic for your weekend getaway!

The correct answer is Either.

We use either before a singular noun ("option") to mean "one or the other" of two choices.

"Both" requires a plural noun ("options"), "Neither" gives a negative meaning that conflicts with "sounds fantastic," and "Every" is used for three or more things.