In Order to Activatthcell Mediatarof Thadaptivimmunresponse, Which of Thfollowing Must

In order to activatthcell mediatarof thadaptivimmunresponse, which of thfollowing must occur?

A) A naïve helper T cell must bind to an antigen-presenting dendritic cell.
B) A naïve B cell must be activated in order to activate the effector helper T cell.
C) A free bacterium must pass through a lymph node where it will directly activate the effector helper T cell.
D) A damaged or infected body cell must pass through a lymph node in order to activate T cells.
E) None of these will activate the cell mediate arm.