The nurse teaches a client about the effects of diphenhydramine (Benadryl), which has been prescribed as a cough suppressant. The nurse determines that the client needs further instruction if the client makes which statement?

a) "I will take the medication on an empty stomach."
b) "I won't drink alcohol while taking this medication."
c) "I will use sugarless gum, candy, or oral rinses to decrease dryness in my mouth."
d) "I won't do activities that require mental alertness while taking this medication."