All of the Following Were Direct Benefits Reaped by the Americans

All of the following were direct benefits reaped by the Americans from the mercantile system of Britain except  

A) British allowed the Americans to freely trade with other countries and compete on the open market.
B) London paid high prices for ship parts to American producers.
C) Virginia tobacco planters enjoyed a monopoly in the British market.
D) protection of the world's mightiest navy and army without a penny of cost.
E) some British merchants were not allowed to compete with the American colonial merchants.