As a result of general sheridan’s use of the total war strategy during the shenandoah valley campaign, the south
retaliated by marching to the sea.
could not provide supplies for its army.
surrendered and brought an end to the war.
vowed to destroy civilian resources in the north.

The answer was the South could not provide supplies for its army. Sheridan applied a “scorched earth” campaign in the valley.  He had burned and destroyed anything that could be of use to the rebels.  Though General Jubal Early launched a surprise attack that caught the Union off guard, Sheridan rallied the men and turned the tables defeating Early and the Senandoah Valley was closed to the South.

the answer would be c

president carter called the victims of kidnapping "victims of terrorism and anarchy" and added that the united states was not going to give in to blackmail. in the united states, they see hostage-taking as an outrage on the part of the islamist movement that violated the principle of international law on the immunity and inviolability of diplomats and their embassies.

carter refused to yield to the demands, khomeini used the situation to consolidate his power and nullify the challenges of the moderate wing of his government, headed by its president. the euphoria over the humiliation of the most powerful nation distracted the iranian people from the economic difficulties of their country. carter, in april 1980, broke diplomatic relations with iran and imposed a trade embargo, except medicine and food. iranian funds in the us they were frozen and accounted for to compensate the hostages when they were released and to pay the demands of us companies against iran.