Factors That Determine the Pathogenicity and Increase the Virulence of Organisms

Factors that determine the pathogenicity and increase the virulence of organisms include all the following EXCEPT:

A) An organism's ability to avoid phagocytosis
B) An organism's ability to produce exotoxins and extracellular enzymes
C) An organism's ability to produce infection when host conditions change
D) An organism's ability to survive intracellularly when phagocytized