Originally Posted by Harmon

It's from The Naked Gun. Detective Frank Drebben commandeers a car that is being driven by a student driver and her instructor in order to chase down a suspect.

She ends up going the wrong way up a one way ramp and ends up having to put the car in reverse and back up quickly in order to keep from being hit by a semi truck.

The truck driver subsequently yells at the student driver calling her a "dumb broad" in which time her instructor tells her to flip him the finger. This is th reaction to him seeing her flip her the bird.

Here is the clip: