Final answer:
Cesar Chavez and the United Farm Workers (UFW) campaigned against the use of deadly pesticides to protect farmworkers from health hazards and to promote safer working conditions.
Step-by-step explanation:
Cesar Chavez and the United Farm Workers (UFW) fought to ban the use of deadly pesticides on crops as part of their broader struggle for the rights of farmworkers. While their activism covered a range of issues related to labor rights, workplace safety, including the use of hazardous pesticides, was a significant concern. These pesticides not only posed severe health risks to the migrant farmworkers who were often exposed to them without adequate protections but also represented a broader environmental and public health issue. The UFW's efforts were rooted in addressing unequal labor conditions and systemic injustices faced by largely Latino agricultural workers. The push to ban dangerous pesticides was aligned with their mission to improve the working and living conditions for these workers, ensuring safe practices in the fields where they labored.