Based on the exhibit, which alert type should the administrator create to detect when Azure marks the storage account unhealthy because of a platform issue?
Resource Health alerts are intended for platform-level availability problems reported by Azure itself. They are the right fit when the business wants to know that Azure has marked a resource unhealthy or unavailable, rather than watching an application metric or a custom log entry. This directly matches the requirement for platform issue notification on the storage account.
Why this answer
Resource Health alerts are specifically designed to notify administrators when an Azure service or resource becomes unhealthy due to platform issues. In this scenario, the storage account being marked unhealthy by Azure due to a platform issue is exactly the kind of event that a Resource Health alert captures, as it monitors the health status of Azure resources and triggers alerts on state transitions (e.g., from 'Available' to 'Degraded' or 'Unavailable').
Exam trap
The trap here is that candidates often confuse Resource Health alerts with metric alerts or log search alerts, mistakenly thinking that any health-related event can be captured by querying AzureDiagnostics or by setting a metric threshold, when in fact Resource Health alerts are the dedicated mechanism for platform-issue notifications.
How to eliminate wrong answers
Option A is wrong because a metric alert on account capacity monitors storage usage thresholds (e.g., percentage of used capacity), not platform health issues; it would not detect when Azure marks the resource unhealthy due to a platform problem. Option C is wrong because a log search alert against AzureDiagnostics queries operational logs for specific events (e.g., authentication failures), but it does not natively capture the resource health state transitions that indicate platform-level unhealthiness; Resource Health events are logged in the Azure Activity Log, not in AzureDiagnostics. Option D is wrong because an autoscale rule based on storage transactions is used to scale resources like Azure Functions or App Service based on transaction counts, not to detect health issues; storage accounts themselves do not support autoscaling based on transactions, and this option is irrelevant to health monitoring.