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: airport : car. mars : ?

A: spaceship
****
Q: portland : car. hotel : ?

A: taxi
****
Q: airport : car. moon : ?

A:
rocket
****