Tempest in a Tea Cup

Two women take seats in a coffee shop. The waiter asks whether they would like coffee or tea.

The first woman says, "I'll have tea."

The other one, who is slightly fastidious, says, "Me, too. And be sure the cup is clean!"

The waiter leaves to fill the order and comes back with two cups on a tray.

"OK, ladies," he says. "Two teas. Which one had the clean glass?"