Answer: The number that represents the time period in which the Civil War ended is (C) 4.
Explanation: The number 4 in the picture represents the time period that extends from 1860 to 1870. At the same time, this time period includes the year in which the Civil War ended: 1865. The Civil War, which was fought between the Union (the forces in the North) and the Confederacy (the forces in the South), started in 1861 and ended in April 1865, when General Robert E. Lee, the commander of the Confederate States Army, finally surrendered after the Appomattox campaign.