True or False: Amazon EC2 instances are immediately available for use once the OS has booted and status checks are passed.

The statement is true: Amazon EC2 instances are indeed available for use once the operating system has successfully booted and all associated status checks have passed.

When an EC2 instance is launched, it goes through a series of initialization processes, which culminate in the booting of the operating system. Once this process is complete and the instance is running without errors, the instance is considered ready for use. At this point, users can access the instance via SSH for Linux or RDP for Windows and start deploying applications or services.

This is fundamental to understanding AWS's on-demand cloud infrastructure, where the speed of instance provisioning and availability is a significant advantage. Instances that pass their health checks are thus reliable for immediate workloads.

Other possible choices do not apply here since the availability of an instance does not depend on any unspecified conditions, nor is it ambiguous or reliant on different instance types in this context. The operational readiness of EC2 instances follows a clear and consistent pattern across all types once the OS has booted and checks are satisfactory.