Cardona found a button marked "B," knew that it meant the basement floor.

Dude pressed a button marked "B"; the descent ended when they reached the basement.

It looked kind of complicated to operate, but then she saw the button marked "automatic," and switched to that setting.

I must have these buttons marked.

She watched him press the button marked "20" and waited as the doors slid soundlessly closed.

(The button marked A on the artist's sketch.)

A character test: Do you hit the button marked "close door" or "open door"?

They went into a small elevator car, and Ken pushed a button marked '3'.

I summon an elevator, press the button marked "4" and proceed to the top floor.

A button marked with a little picture of a car.