The storage classes that best meet the requirement of high availability and resilience even in case of a regional outage are Multi-Regional and Dual-Regional. These storage classes replicate data across multiple regions, ensuring that even if one region experiences an outage, the data remains accessible from another.

Here’s a breakdown of the options:

• Standard: Offers a balance of performance and cost, but does not provide regional redundancy.
• Regional: Stores data in a single region and is not suitable for high availability requirements.
• Coldline: Optimized for infrequent access and is not designed for high availability.
• Dual-Regional: Replicates data across two regions within a single geographic area, providing high availability within that region.
• Multi-Regional: Replicates data across multiple regions globally, providing the highest level of availability and resilience.

Therefore, Dual-Regional or Multi-Regional storage classes are the most appropriate choices to meet the company’s requirements for highly available and resilient cloud storage.