Good distractors are reasonable alternatives to the correct answer and are not obviously wrong. This maximizes the mental effort learners must make in choosing an answer.

For example, in the following Activity it’s easy to see the correct answer is “10 days” because the other options are unrealistic. 

How much vacation time will you earn in your first year of work? 

  1. 2 hours
  2. 10 days
  3. 2 months 
  4. 100 days

Keep the answer and all of your distractors similar in length and format. For example, if one answer option starts with a verb, they should all start with a verb; if one option is a sentence, they should all be a sentence. Categorical answers, such as “all of the above” or “none of the above,” are exceptions to this rule. 

For example, this Activity has poor distractors: 

What is the first thing you should do if the fire alarm goes off?   

  1. Leave the warehouse immediately
  2. Yell “Fire” 
  3. Hide 
  4. You should pull the alarm

Some better distractors would be: 

What is the first thing you should do if the fire alarm goes off?   

  1. Leave the warehouse immediately 
  2. Check your surroundings for danger 
  3. Turn off your equipment
  4. Wait for further instructions