Based on historical perspective, the statement that BEST describes the first two years of the Civil War in the Eastern Theatre is "none of the above."
The American civil war occurred between 1861 to 1865. The Union (North) battles the Confederates (South) over succession.
In the early battles, it was the Confederates that won. Battles such as Fort Sumter on April 12 - 13 1861, First Battle of Bull Run on July 21, 1861, etc.
The momentum changed in Union favor when they first won at the Battle of Fort Donelson in February 1862 and most significantly at Gettysburg in July 1863.
Hence, in this case, it is concluded that it was rather Early Confederate's success followed by later Union success in the Eastern Theatre.
Learn more about the American Civil war here: https://brainly.com/question/1020924
