Answer:
d. clustered in the West as agricultural workers.
Explanation:
There were high numbers of Mexican and Asian immigrants in the first decades of the 20th century. Mexicans went usually to take jobs in agriculture. Farmers in the Southwest told the authorities that withouth Mexicans, they wouldn´t be able to harvest their crops. Asian also settled in the West. In the 1920s, immigration quotas were established according to nationalities, in parto to respond to discontent to immigration. However, Mexicans were not included in the quota system and could enter the US to work in farms.