Directions: The sentence below has been divided into four parts. One of the parts may have an error of grammar or diction. Select the part having the error. If there is no error, choose option (e).

(a) The American civil war, the deadliest in American history, caused (b) 620,000 soldier deaths and an undetermined number of civilian (c) casualties, ended slavery in the United States restoring the (d) Union, and strengthened the role of the federal government (e) No error