Final answer:
The military campaign McClellan waged at Richmond was the C) Peninsular Campaign. The campaign culminated in the Seven Days Battles and included the battle of Malvern Hill, after which McClellan retreated without capturing Richmond.
Step-by-step explanation:
The military campaign that McClellan waged at Richmond was known as the C) Peninsular Campaign. McClellan's original plan involved landing his army at Fort Monroe, Virginia and marching them towards Richmond.
His plan was to surprise the Confederates by attacking from the east but he encountered significant obstacles including Confederate defenses and inclement weather.
General Lee took command after General Johnston was wounded, and he prepared the Confederate defenses against McClellan's forces.
The campaign included several battles, notably the Seven Days Battles, and despite initial advantages, McClellan's retreat marked a failed opportunity to capture Richmond and possibly end the Civil War earlier.
After the Seven Days Battles, McClellan retreated to Harrison's Landing, and despite heavy Confederate losses at the Malvern Hill battle, he chose not to attempt another advance on Richmond.
General Lee's defense of Richmond was successful, and he shifted his focus to a campaign in Maryland, as McClellan maintained command over his forces after the retreat.