The correct answers are:
a. lowering unemployment;
- The corporations in the United States became enormous, and as they grew bigger and bigger, they were opening more and more working places, thus helped in lowering the unemployment in the country.
d. larger variety of merchandise;
- As the corporations started to get into pretty much every production sector, and their economic power was becoming bigger, they started to produce much bigger variety of products for the market.
e. lowering prices;
- Since the corporations are producing on a very big scale, in very economically justified way, they were able to lower the prices for lots of products, and that helped them grow even bigger because the customers in general prefer the lower prices.