Answer:
Grain sub-treasury has multiple purposes or plans regarding the currency/ money issue for farmers. Some of the effect of grain sub-treasury on the currency/ money issue for farmers are as following:
- Farmers were no more dependent on local merchant, grain elevator and other warehouses for money lending.
- Because of grain sub-treasury farmers are now able to hold their crops for long to sell at better price.
- Grain sub-treasury plan expand the amount of money in circulation.
- Grain sub-treasury has increased the price of food or grains.
Hence, grain sub-treasury plan was beneficial for farmers.
I believe they’re referring to the Tuskegee Airmen. Here a link to an article about them https://www.google.com/amp/s/www.history.com/.amp/topics/world-war-ii/tuskegee-airmen
B. Other two don't make sense.
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