This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
True about ythT cells: 
Select and explain. 
A. Are helper t cells, B. Oligoclonal proliferation, C. Antigen presentation, D. Opsonization
B: Oligoclonal proliferation
Answer: B: Oligoclonal proliferation 
Explanation: Ans: B. Oligoclonal proliferationCell TypeSubsetMain mediatorsEstablished roleFindings in allergic rhinitis (AR)gd T cell* IFNg * IL-17A * IL-17F* IL-22* proinflammatory and immune-modulating functions at epithelial surfaces* innate and adaptive immunity paicipation* ydT cytokines induce B cell IgE synthesis* suppo Th2 inflammatory response* oligoclonal proliferation in nasal mucosa (?)* | circulating ydT cell percentages correlating with Th17 numbers in AR* negative correlation with Tregs