[单选题]
This diagram shows the interaction betwep* w9u7,w tfbven a helper T-cell and a(;;(qv cmzf6mu*ylzi B-lymphocyte.
A. Histamine
B. Antibody
C. Antigen
D. Killer T-cell
参考答案: C
本题详细解析:
Explanation:
Choice C is correct because antigens activate Helper T-cells when they bind to them and these then activate B lymphocytes. Choice A is incorrect because histamine is produced by mast cells. Choice B is incorrect because antibodies are proteins produced by B-lymphocytes. Choice D is incorrect because killer T-cells are white blood cells that destroy infected body cells.