Of the choices listed, only imiquimod (c) is an immunomodulatory agent. It is an inducer of cytokines of innate immunity, stimulating production of IFN-a, tumor necrosis factor, interleukin-1, and interleukin-8. It can be used in conjunction with physical removal of HPV outgrowths to prevent viral replication in any remaining infected cells. Acyclovir (a) is an antiviral specific for HSVs and VZVs, which have viral thymidine kinases to activate the drug. 5-Fluorouracil (b) is a cytotoxic agent that interferes with RNA and DNA synthesis, podophyllin (d) is a cytotoxic agent that is anti-mitotic, and trichloroacetic acid (e) is a keratolytic agent that chemically cauterizes skin, keratin, and other tissues. The latter three agents can all be used in treating condyloma accuminatum, but they are not immunomodulatory.