Which of these does not describe a custom?
A
It's common in many societies in the US to say "bless you" when someone
I!
sneezes.
B
In Canada, it's customary to leave 15-20% of a bill at a restaurant as a tip for
server.
с
It's considered rude in Japan to pass food with chopsticks.
D
It's common when taking cold medicine to feel tired.