单项选择题
Virally
infected host cells are tagged with antigen-antibody complexes.
These complexes recruit NK cells that trigger apoptosis in the
infected host cell.This is an example of: ____
A．antibody-dependent
cell-mediated cytotoxicity
B．antigen
presentation
C．complement
fixation
D．neutralization
E．opsonization
A. 
B. 
C. 
D. 