You are operating an IoT infrastructure of a large manufacturing facility where, for technological reasons, the temperature and humidity of the workspaces must be strictly controlled. The facilities are already equipped with hundreds of sensors but now you need to add 20 sensors and connect them via a transparent edge gateway to the cloud. The existing infrastructure is managed through IoT Central and it must be used in the future, as well. 
When implementing this scenario, which of the following statements is true?

Answer options:

A.For downstream devices you don’t need a device template in IoT Central
B.Downstream device identities don’t need to be created in IoT Central
C.The devices must connect to the Thermostat module on the edge device
D.The devices must connect to the edge device, not to its modules

Correct Answer: D
Option A is incorrectbecause yes, in a transparent gateway scenario, the downstream devices need to be created in IoT Central, i.e. an appropriate device template is needed.
Option B is incorrectbecause yes, in a transparent gateway scenario, the downstream devices need to be created in IoT Central.
Option C is incorrect because it is the translation gateway scenario where devices connect to specific (translation) modules hosted on the gateway device. In this particular case, the devices connect to the edge device itself.
Option D is CORRECTbecause in transparent gateway scenarios the leaf devices connect to the gateway device itself.
Diagram: 

Reference: 

https://docs.microsoft.com/en-us/azure/iot-central/core/how-to-connect-iot-edge-transparent-gateway