Which civil war general's name would accurately complete the list above?

Here is the full name list for this question:

George McClellan
Henry Halleck
Joseph Hookker
George Meade


I believe the answer is: Ulysses S. Grant

All the name above are the generals who fought for the union side. From the name above, Ulysses Simpson Grant probably held in highest regard due to his huge contribution in defeating the confederate army. As a reward, President Abraham Lincoln made him the commander of all the generals.