The correct answer is B because Managed Instance Groups offer the AutoHealing feature. This feature conducts health checks and automatically recreates any instance where the application is unresponsive. This ensures high availability by proactively maintaining instances in a RUNNING state and addressing application-specific issues like freezing or crashing.

• Option A is incorrect as auto-updating is for deploying new software versions, not for ensuring instance health.
• Option C and Option D are incorrect as these features do not exist within the context of managed instance groups.

For more details, refer to the GCP documentation on Managed Instance Groups and Autohealing.