This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skin, Subject name: Pathology
A 35-year-old man has noted a small bump on his upper trunk for the past 6 weeks. On physical examination, there is a solitary, 0.4-cm, flesh-colored nodule on the upper trunk. The dome-shaped lesion is umbilicated, and a curd-like material can be expressed from the center. This material is smeared on a slide, and the Giemsa stain shows many pink, homogeneous, cytoplasmic inclusions. The lesion regresses over the next 2 months. Which of the following infectious agents most likely produced this lesion? 
Select and explain. 
A. Histoplasma capsulatum, B. Human papillomavirus, C. Molluscum contagiosum, D. Staphylococcus aureus
C: Molluscum contagiosum
Answer: C: Molluscum contagiosum 
Explanation: The pink cytoplasmic inclusions, called molluscum bodies, are characteristic of this lesion. Immunocompromised individuals may have multiple, larger lesions. The infectious agent is a poxvirus. Disseminated fungal infections such as histoplasmosis involving skin are uncommon except in immunocompromised patients. Human papillomavirus (not a toad) is implicated in the appearance of verruca vulgaris or the common wart. Staphylococcus aureus is implicated in the formation of the lesions of impetigo and pustular skin infections. There are a variety of superficial fungal infections caused by dermatophytes, such as Tinea corporis producing a scaling plaque. Varicella-zoster virus causes shingles, characterized by a dermatomal distribution of clear, painful vesicles.