You have just created a device identity in your IoT Hub named , using the following CLI commands: 
<pre class="brush:java;">az extension add --name azure-iot 
az iot hub device-identity create 
 --device-id TempSensor-001 
 --hub-name {mytemphub-001}
</pre>
So that your device can successfully connect to the IoT hub, all you need is the device-id in your device code. 
Is this statement true?

Answer options:

A.Yes
B.No

Correct Answer: B
Option A is incorrect because the device id alone is not sufficient for the device to connect. So that the device can establish connection to the IoT Hub, it needs the device connection string assigned to its identity upon creation in the IoT Hub. Using Azure CLI, you can get it by a command like this:
<pre class="brush:java;">az iot hub device-identity connection-string show --hub-name mytemphub-001 --device-id TempSensor-001 --output table</pre>Option B is CORRECT because it is the device connection string that the device actually needs to be able to connect to the IoT Hub. It looks like this:
<pre class="brush:java;">HostName=mytemphub-001.azure-devices.net;DeviceId=TempSensor-001;SharedAccessKey=WCXEysQ1234…...</pre>
Reference: 

https://docs.microsoft.com/en-us/azure/iot-hub/quickstart-control-device-python#register-a-device