Skip to the part where Bunsen and Beaker (the green pea man and the pink thing) have just asked Scrooge for a donation to the poor.

When Scrooge is kicking them out the door, Bunsen says something like "Lets go Beaker, I'm sure we've used some of Mr SCROOGE'S time!" After this sentence, Bunsen walks out of the door and Beaker is left facing Scrooge, and gives, from what I can see, the finger.

Its unclear at first glance whether he points the index, or the middle finger.