30. Which of the following statement about innate and adaptive immune systems is NOT true? (A) In Drosophila melanogaster, recognition of an invading pathogen activates the Toll or Imd signaling pathway. (B) Mammalian Toll-like receptors are activated by different pathogen-associated molecular patterns. (C) B cells are cellular origins of antibody immunity but not professional antigen-presenting cells. (D) T cells, B cells and antibodies constitute major components of adaptive immunity.