Which statement describes a model class that extends Mage_Core_Model_Abstract?

A.
The model class consists of properties and methods for storing and manipulating data retrieved via
separate resource classes responsible for database operations.

B.
The model class is responsible for loading the frontend layout templates and responding to page requests
via its Action methods (for example, indexAction).

C.
The model class does not encapsulate any logic except for logic providing access to the data loaded from
the database.

D.
The model class is primarily responsible for direct query operations such as retrieving and storing data and
then rendering that data to the frontend view.