A nurse needs to administer a cephalosporin to a client. The client informs the nurse that he is allergic to penicillin. Which action by the nurse would be most appropriate?

A) Administer the cephalosporin without concern
B) Administer a small test dose of cephalosporin
C) Withhold the cephalosporin and notify the provider
D) Ask the client to describe the penicillin reaction