Final answer:
Non-Hodgkin's lymphoma (NHL) is the most common malignancy linked to paraneoplastic pemphigus in children, with lymphomas being more frequently associated with this autoimmune condition than other pediatric cancers.
Step-by-step explanation:
The most common malignancy associated with paraneoplastic pemphigus in kids is non-Hodgkin's lymphoma (NHL), making option C the correct answer. Paraneoplastic pemphigus is a rare autoimmune blistering disorder that can be associated with various malignancies. In the pediatric population, it is most frequently associated with lymphomas, including NHL. While neuroblastoma, acute myeloid leukemia, and Wilms tumor are also childhood cancers, they are less commonly associated with paraneoplastic pemphigus compared to NHL.