The united farm workers union would have been most concerned with the plight of a) small farmers. b) migrant workers. c) industrial farmers. d) mid-western farmers.

I believe the answer is: B.migrant workers.

At that time, the migrant workers was forced to live under a horrible condition since there was no laws that regulate company's treatment toward of its employees. Due to the plight of these workers, united farm workers was created in order to create better situation for the migrant workers.

The United Farm Workers union would have been most concerned with the plight of migrant workers.

Thus Option B is correct.  

Explanation:

The United Farm Workers union would have been most worried with the situation of migrant workers.  During the period of 1930s thousands of farmers migrated to California as they lost everything in a natural disaster. They had nothing to eat no other source to live there.

The Farmers who took the lands on rent were not able to pay their rents. All these things created a lot of burden on the lives of farmers and a result of this they migrated to California in search of life and living hood.  

explanation:

allergens: overstimulate the nerve system

neurotics: attack nerve cells

mutagens: damage or otherwise alter dna sequence

generators: cause defects during growth and development  

carcinogens: cause unchecked cell growth

i hope you get the idea according to me these are the effects that happened.