Of the Following Goals Listed, Which Are the Two Goals

Of the following goals listed, which are the two goals of epidemiology?
I. isolate the infectious pathogen for study and vaccine creation
II. describe the nature, cause, and extent of new or existing diseases in populations
III. identify patient zero and how the initial infection occurred
IV. intervene to protect and improve health in populations
V. distribute vaccines so that future outbreaks do not occur

A) I and II
B) III and V
C) II and IV
D) I and III
E) III and IV