Which cloud capability allows a database to automatically scale during seasonal traffic spikes?

Elasticity is the correct answer because it refers to the ability of a cloud system to automatically scale resources up or down to meet demand, without manual intervention. This is precisely what is needed for seasonal traffic spikes, where resources are added when demand increases and removed when demand decreases. Fault tolerance ensures an application remains available despite component failures, but doesn't directly address scaling for traffic. Agility refers to the ability to rapidly develop, test, and deploy applications, which is a broader benefit of cloud computing but not specific to automatic scaling for demand. Metered pricing is a billing model where you pay only for the resources you consume, which is a characteristic of cloud services but not a capability that enables automatic scaling.