When Performing Oral Care on an Unconscious Client, Which of the Following

When performing oral care on an unconscious client, which of the following prevents aspiration of fluids into the lungs?

A) Put the client on a side-lying position with the head of bed lowered.
B) Keep the client dry by placing a towel under the chin.
C) Wash hands and observe appropriate infection control.
D) Clean the client's mouth with oral swabs in a careful and an orderly progression.