How did the sinking of the Lusitania in 1915 affect World War I?
The United States immediately declared war on Germany.
Germany continued its policy of unrestricted submarine warfare.
Many Americans demanded that the United States enter the war.
The United States began a policy of unrestricted submarine warfare.

C) Many Americans demanded that the United States enter the war

Explanation:

The attack on the Lusitania, a passenger ship with civilians on board, by a military submarine signaled the end of the more "civilized" warfare of the 19th century. It also proved to be a powerful propaganda tool for turning American public opinion against Germany and in support of joining the war.

the following best describes postwar era writers in their works:

many writers,authors,novelists,poets concentrated more on social art and social writing and stayed away from political writings.

i believe the correct answer is option b. most eastern european nations joined nato.

though i could be wrong, option d. the eastern european nations were granted complete independence, would be another choice.

hope this ! : )