At this stage, you need to author good distractors for each question. A distractor is a wrong answer meant to confuse a learner.
Here are some tips:
Make all response options clear and concise. There’s no reason to have multi-paragraph answers.
Keep answers and distractors the same structure and length. Any inconsistencies in grammar and language choice can provide unwanted clues to the correct answer.
Don’t constantly rely on answer options like “none of the above” and “all of the above”, especially on multiple choice questions.
Avoid options where users’ answers can be counted “wrong” by mistyping or misspelling the answer: “Chicago” and “chicago”, “Carroll” and “carroll”. After all, if the employee types the right word but uses the wrong case, the final score will be biased if the quiz is case-sensitive.
Ensure your answers are absolutely correct and distractors definitely wrong. Any inaccuracy with either the subject or the phrasing of the response options will confuse your learners.