There was little rainfall for several years.
Answer: Option 3
Step-by-step explanation:
During the time of 1930s, there was severe drought in the United States of America because of the lack of rainfall for many years. Because of this there was wind erosion. Moreover the farmers of that area did not apply the dry land farming also.
The time period of dust storm led to huge disaster and destruction in the ecology and to the environment of the American and Canadian prairies. This added more to the great depression and strengthened it even more because the production of food was also badly affected. Thus time period was known as the dirty 30s.