Which of the following statements about HubL in modules is TRUE?

Module fields are integrated into a module's HTML markup using HubL. This allows developers to define editable content areas within a module that content creators can then populate in the page editor. For example, {{ module.mytextfield }} would display the content of a text field named mytextfield. Modules do not strictly require custom HubL; they can be published with only HTML and CSS, or even be empty. HTML attributes can contain HubL code, for instance, <img src="{{ module.imagefield.src }}". The drag and drop editor is for arranging modules and content, not for writing HubL code within a custom module; HubL for custom modules is written in the code editor.