Finish the following sentence with the best choice: How can I keep my bartender from getting rid of my drink if I have to go to the bathroom quickly?

Choices:
- Place a coaster on top of your drink, this is universal sign for "I'll be back".
- Place a coaster under your drink, this is universal sign for "I'll be back".

Answer:
Place a coaster on top of your drink, this is universal sign for "I'll be back".