What was one of president lincoln's major frustrations early in the civil war? a. overly aggressive military leaders b. too many railroads to defend effectively c. lack of manpower d. lack of aggressive military leadership

During the Civil War, President Lincoln appointed George McClellan as General and he must play an important role in raising well-trained and organized army. 

Though General McClellan did a great job in developing and training armies, he was known to be indecisive and seems to lack aggressive military leadership.