During World War I, the War Industries Board:

(A) controlled the entire war mobilization effort.

(B) was led by Herbert Hoover.

(C) oversaw the production of America's factories.

(D) failed to lead American industry effectively.

(E) was concerned with building new munitions plants.

The correct answer is A. During World War I, the War Industries Board controlled the entire war mobilization effort.

Explanation:

The War Industries Board was an American government agency existing from July 28, 1917 to November 30, 1918, whose task was to organize and coordinate the work of the American industry and the purchase of war supplies and weapons, in order to win the First World War.