The correct answer is C. Etanercept.
This woman has Stevens-Johnson syndrome (SJS) secondary to lamotrigine. The treatment of SJS/TEN is controversial and variable given the paucity of high-quality data. Nevertheless, publications exist that support the use of various immunomodulators, including etanercept, prednisone, IVIG, and cyclosporine. Etanercept is the only one of these options that is pregnancy category B, indicating animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.
Prednisone, IVIG, and cyclosporine are all pregnancy category C (animal studies show a fetal risk and there are no adequate human studies) and therefore carry a theoretically increased fetal risk compared to etanercept. Rituximab is not used in the treatment of SJS/TEN, and is also pregnancy category C.