It would have to be: Make sure that you have clearly explained what happened, how it happened, and why.
Answer:
C is the answer.
Explanation:
A is wrong because "bologna sandwich on Mondays", "ham sandwich on Tuesdays", and "turkey sandwich on Wednesdays" is parallel.
B is wrong because "toilet runs, icemaker is broken, and faucet drips" is parallel.
C is correct because the 2 "how-to"s mess it up. If it were parallel, the third clause would also have a "how to".
Answer: A
Explanation: I don't really have an explanation besides that fact that my grandmother calls her cabinets and draws in her kitchen a buffet lol.