This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'MHC class III genes encode - \nSelect and explain. \nA. Complement component C3, B. Tumor necrosis factor, C. Interleukin 2, D. Beta 2 microglobulin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: class 3 or complement components C2& C3 of the classical pathway, as well as properdin factor B of the alternate pathway, heat shock proteina & tumor necrosis factor alpha& beta Reff: Ananthanarayanan & Panikers textbook of microbiology 9th edition pg:140', 'role': 'assistant'}]