So you pick up your friend every morning at 7 and drive into work together. You drive over to his apartment complex at the scheduled time. It's cold out and you want to let him know you've arrived. Do you:
A. Get out of the car and knock on his door?
B. Call from your cell phone?
C. Sit there hoping he notices your arrival?
D. Blare on the horn waking up anyone in the complex who may still be sleeping?