If you ever need to create a multiple choice exam, take a look at guides to guessing the correct answer. Next, design your exam work against those common assumptions.
This way you'll be able to experience the joy of seeing many scores below 25% on an exam with only multiple choice questions (each of them being single choice with 4 options).
[This is under the assumption that any exam held as pure multiple choice can't be taken too seriously and isn't that important]
Here's one guide for reference:
3.uwsp.edu/tlc/Documents/Educated%20Guessing%20Strategies%20(1)
(I'm certain links will get f1@ gged, so just add 3 "w" at the beginning and ".pdf" at the end)
Example question:
What should be put inside a hotdog bun?
A. a hot log
B. a hot pocket
C. always a wiener
D. sometimes, any kind of meat is alright, except for dolphin