What is the author's main purpose in "The Fight in the Fields: Cesar Chavez and the Farmworkers' Struggle?"

A
to describe Cesar Chavez's life
B
to explain how unions work
C
to explain how Cesar Chavez helped solve the farmworkers' struggle by creating a union
D
to describe the problem that farmworkers were facing
PART B

C - to explain how Cesar Chavez helped solve the farmworkers' struggle by creating a union