Final answer:
Rescission can happen automatically when material facts are not disclosed in a contract, such as a vehicle's mileage, as it is central to the vehicle's value and expected to be disclosed. It does not automatically occur for other non-disclosed facts like accident history, ownership records, or service history.
Step-by-step explanation:
Rescission is a remedy in contract law that allows a contract to be rendered void and can occur automatically in certain circumstances. This is often applicable in cases where material facts are not disclosed. In the context of a vehicle sale, there are multiple facts that might be considered material, such as accident history, mileage, ownership records, and service history. However, rescission does not automatically occur for failing to disclose each of these. Instead, rescission typically applies to situations where there has been a misrepresentation that goes to the heart of the contract. Among the options provided, (b) Vehicle's mileage would be a fact where nondisclosure could most likely lead to an automatic rescission, as it is a central aspect of the vehicle's value and condition that is expected to be disclosed in a transaction.