In general, no, the revolution in agriculture was no necessary to the Industrial Revolution since the Industrial Revolution relied on things like machines and steel.
The correct answer is Ravenna.
That is because Ravenna was a city that was reconquered by the Byzantine empire after it originally fell to the Ostrogoth when the fall of the Western Roman Empire occurred. It was a capital for western Romans and for the Ostrogoth, but it wasn't for the Byzantine people who had their own capitol even after they reconquered it.
A lot of historians believe the battle of Fort Sumter was the start of the war, as it was the first official battle. However, there were zero casualties.
A lot of other people believe when Lincoln was elected was the start, because that event led many southern states to secede very quickly.
