Final answer:
Resource groups cannot be nested, which makes option C the correct answer. Resource groups are used to organize related resources and they support role-based access control and movement of resources between groups.
Step-by-step explanation:
The correct answer to the student's question is C. Resource groups cannot be nested. When dealing with resource groups within cloud platforms such as Microsoft Azure or Amazon Web Services (AWS), it's important to understand the properties that define them. A resource group is a container that holds related resources for an Azure solution. The resource can only exist in one resource group at a time, and it is indeed possible to move resources from one group to another. Additionally, access control policies can be applied to resource groups using role based access control (RBAC) mechanisms to manage permissions efficiently.