You need to connect your IoT device to the IoT Hub by using the open-source SDKs. You’ve got a script as a template, which you need to customize with the connection method to link your device to the device identity: 
<pre class="brush:java;">...
# The client object used to interact with your Azure IoT hub
device_client = IoTHubDeviceClient.create_&lt;...insert code here...&gt;
# Connect the client.
await device_client.connect()
... </pre>
Which is not a valid connection method?

Answer options:

A.… from_x509_certificate
B.… from_connection _string
C.… from_primary_key
D.… from_symmetric_key

Correct Answer: C
Option A is incorrect because you can instantiate a client using theX509 certificate by the create_from_x509_certificate method of the IotHubDeviceClient class.
Option B is incorrect because you can instantiate from the IoT Hub connection string of the device, by the create_from_connection_string method of the IotHubDeviceClient class.
Option C is CORRECT because the Primary key is the name of the symmetric shared access key of the device in the IoT Hub. It is not a valid method name in the SDK.
Option D is incorrect because you can instantiate symmetric key authentication by the create_from_symmetric_key method of the IotHubDeviceClient class.
Diagram: 

Reference: 

https://docs.microsoft.com/en-us/python/api/azure-iot-device/azure.iot.device.iothubdeviceclient?view=azure-python