Final answer:
Main points in an outline are typically indicated by Roman numerals, which help in structuring the information clearly. The Correct multiple-choice option is (a) Roman. It helps in making the outline clearer and more effective for studying or presenting information.
Step-by-step explanation:
In an outline, main points are indicated by Roman numerals. In this context, Roman numerals (I, II, III, IV, etc.) are typically used to organize and present the hierarchy of information in a structured and systematic manner, which helps in making the outline clearer and more effective for studying or presenting information.
The Correct multiple-choice option is (a) Roman.