47. 腸道黏膜層的M細胞(microfold cells)是一種什麼細胞?(A)抗原呈現細胞(antigen-presenting cells)(B)內分泌細胞(endocrine cells)(C)黏液分泌細胞(mucus-secreting cells)(D)吸收性細胞(absorptive cells)