Journey by Stephen Clark  
    to Ridgetown

The alien nods approvingly and the ship takes off.
    While in space, you are trying to blend in and act casual when suddenly the whole ship is rocked by an explosion. "Oh no!", says an alien named reftak. "It's a Fnorlian warship attacking us! The Fnorlains are our sworn enemies! Quick, turn on the shields!"
    This last comment is addressed to you. You look at the cryptic control-panel in front of you.
Press the black button
Press the white button