His 1930 tariff was passed with the goal of protecting the american economy, but in reality it reduced u. s. imports and exports by as much as 50%.

d is the correct answer.

b is incorrect because it makes food by itself

c is incorrect because us humans don't know how to produce their own food using the sun like plants.

a is incorrect because consumers can depend on carnivores for eating food for consumers to eat the dead organism. same thing with omnivores.

it continues in business