A patient with cancer is undergoing chemotherapy and develops a fever of 103.5; he is found to have a neutrophil count of 300/mm3. Physical exam is not helpful in pinpointing the source of infection. Cultures are pending. Appropriate initial empiric antibiotic therapy might include the following EXCEPT:
a. A chphalosporin.
b. An antipseudomonal penicillin.
c. Vancomycin.
d. A fluoroquinolone.