The following are multiple choice questions (with answers) about medical knowledge.   **Question:** An 8-year-old girl comes to the physician because of a 2-day history of hematuria. Two weeks ago, she had a sore throat that resolved without treatment. Physical examination shows 1+ pitting edema of the lower legs and ankles. Urinalysis shows numerous RBCs and 3+ proteinuria. Her antistreptolysin O titer is elevated. Formation of which of the following is most likely involved in the underlying mechanism of this patient's symptoms?   (A) Antigen-specific IgE binding to mast cells   (B) Tissue-specific antibodies   (C) Antigen-antibody complexes   (D) Presensitized CD8+ cytotoxic T-cells
['(C) Antigen-antibody complexes <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Antigen-specific IgE binding to mast cells \n (B) Tissue-specific antibodies \n (C) Antigen-antibody complexes \n (D) Presensitized CD8+ cytotoxic T-cells <> possible answers', "  An 8-year-old girl comes to the physician because of a 2-day history of hematuria. Two weeks ago, she had a sore throat that resolved without treatment. Physical examination shows 1+ pitting edema of the lower legs and ankles. Urinalysis shows numerous RBCs and 3+ proteinuria. Her antistreptolysin O titer is elevated. Formation of which of the following is most likely involved in the underlying mechanism of this patient's symptoms? <> context@"]