As a resident physician in radiology, I was speaking with the man whose wife was about to receive a CAT scan of the chest.
While the nurse was placing the intravenous line, I asked the husband if his wife had undergone any other tests. The man named several procedures involving various body parts, but he couldn't remember one particular test.
Thinking out loud, he said, "What is that thing women have that men don't?"
His wife was quick to answer, "A brain, dear."