Medical Samples

An old man and his wife went to the doctor's office. The doctor asked the man for a blood, urine and feces sample.

The man was slightly deaf and said, "What?"

The doctor said, "I need a blood, urine and feces sample."

The man still looked puzzled, so his wife leaned over and yelled into his ear, "Sheldon, the doctor needs a pair of your underwear."