The answer would be letter A, consistent symbols. It is because the need of consistent is not really a requirement for doing an outline for it is only a representation or a plan of what you're doing before you do the actual work. The rest are important things to do in an outline for using your notes is important for it is a reliable source and a simple sentences because an outline does not require long sentences unless only necessarily. Use of ANSVA is also important because as how the acronyms means, Attention, Need, Solution, Visualization and Action is needed in doing your outline.
