20. What do all outlines, whether formal or informal, have in common? A. They list all the information you'll present in the order you'll present it. B. They use Roman numerals and Arabic numbers. C. They're required parts of academic essay assignments. D. They're written in complete sentences with proper punctuation. Select the best answer for the question. 18. A/an outline is one that uses some combination of Roman numerals, letters, and/or Arabic numbers. A. natural B. formal C. informal D. logical