Answer:
A. To show the reader the necessary steps to complete the project
Step-by-step explanation:
A subheading is a subsection or title of a piece of literary work. It is used to introduce a part of a text.
A project plan is a document that contains the scope and objectives of a project.
The purpose or function of a subheading in a project plan cannot be overemphasized because it breaks down the processes involved in a project to simple steps that a reader can glance through and get the fundamentals.