正解:B
Data portability is the ability to move data from one cloud service provider to another without losing functionality, quality, or security. Vendor lock-in is a situation where a customer becomes dependent on a particular cloud service provider and faces high switching costs, lack of interoperability, and contractual obligations. Vendor lock-in can result in data portability issues, as the customer may have difficulty transferring their data to a different cloud service provider if they are dissatisfied with the current one or want to take advantage of better offers. Data portability issues can affect the customer's flexibility, agility, and cost-efficiency in the cloud.