Directions: The following question tests your ability to recognize grammar and usage errors. The sentence contains either a single error or no error at all. No sentence contains more than one error. The error, if there is one, is underlined and lettered. If the sentence contains an error, select the underlined part that must be changed to make the sentence correct. If the sentence is correct, select choice (E). In choosing the answer, follow the requirements of standard written English.

The American civil war, the deadliest in American history, (A) caused 620,000 soldier deaths and (B) an undetermined number (C) of civilian casualties, ended slavery in the United States (D) restoring the Union, and strengthened the role of the federal government. (E) No error