You are operating a fleet of IoT devices consisting of several different types of environmental sensors. Because of some changes in the standards, the maximum temperature limits for the sensors must be updated using the automatic device configuration feature of IoT hub. You are now about creating a configuration for updating your devices. 
Which of the below settings won’t you set as parts of the configuration?

Answer options:

A.Device scope
B.System metrics
C.Target content
D.Custom metrics

Correct Answer: B
Option A is incorrect because the scope of the devices, i.e. the devices that need to be targeted by the configurations is required. It is called “target condition”
Option B is CORRECT because system metrics are included in all configurations by default. You don’t need to (and you can’t) set them manually. System metrics include the number of twins targeted and the number of twins successfully updated. System metrics can be used to monitor the process and the success of the operation.
Option C is incorrect because the setting defining the values to be applied to the given set of devices (i.e. the “target content”) is a required part of the configuration.
Option D is incorrect because, while it is not required, you can define your own custom metrics for automatic configurations, as part of the process.
Reference: 

https://docs.microsoft.com/en-us/azure/iot-hub/iot-hub-automatic-device-management#target-devices