You are maintaining three servers s1.testcomp.com, s2.testcomp.com and s3.testcomp.com. You wanted an alert whenever any of your servers exceeded processor utilization of 80% more than two times over an hour. You created an alert rule in Azure Monitor: 
As per the alert rule, for each of the three servers, average processor utilization is computed for 10 mins. 
You analyzed the query results. Threshold of 80 being breached by s1.testcomp.com at 09:10, 09:20 bins; s2 exceeds 80 thresholds at 09:20, 09:30 and 09:40 bins; and s3 exceeds 80 thresholds at 09:10, 09:20, 09:40 and 09:50 bins. 
The alert fired for only s2.testcomp.com, which is not as per your expectation mentioned above. You want to modify the alert rule so that you get alert for s3.testcomp.com as well if a scenario happens as above. Which one of the following alert rule configurations is needed to modify?

Answer options:

A.Frequency
B.Time period
C.Trigger
D.Threshold

Answer: C 

https://docs.microsoft.com/en-us/azure/azure-monitor/platform/alerts-unified-log