43. A person exposed to a new cold virus would not feel better for one to two weeks because (A) antigen receptors are not the same. (B) phagocytic cells must first be activated by the complement system. (C) it takes up to two weeks to stimulate immunologic memory cells. (D) specific B cells and T cells must be selected prior to a protective response. (E) V-J gene rearrangement must occur prior to a response.