Vendor lock-in is a situation in which a customer using a product or service cannot easily transition to a competitor's product or service. Vendor lock-in is usually the result of proprietary technologies that are incompatible with those of competitors.

GRC and data is responsibility of the customer in all service models according to shared responsibility model.

The answer is False. This is a very tricky question and it has to be read and understood well before answering.
It is always the other way around. Cloud consumer's security increases when you move from Software as a service model to Infrastructure as a Service Model.