Answer:
Option c. Subordination.
Step-by-step explanation:
When creating the body of an outline it is important to include and use correctly a set of techniques. One of them is called subordination, that allows you to convey differences in importance within the body of writing. So when writing a heading and a subheading, subordination means that the information in the headings should be more general while the information in the subheadings should be more specific.