Two analogies that relate places/locations to the associated travel mode is given in the form "A : B. C : ?". "A : B" relates place A to travel mode B. Your task is to replace the question mark (?) with the appropriate travel mode for the given place C, following the "A : B" relation.

Q: washington : airplane. spain : ?

A: airplane
****
Q: mainland : boat. restaurant : ?

A: taxi
****
Q: restaurant : taxi. mars : ?

A:
spaceship
****