Knowledge Check Odditiy

Several weeks ago we opened an online training program. I anticipated that there would be some technical issues along the way. Of the 30 people that have taken the program, one indicated that he had an issue with a video hanging. The second more perplexing problem dealt with a knowledge check. The question asks the respondent to place the following 5 step in the proper order. The participant claims that he only saw 4 answers and not 5. 

Has anyone experienced anything like this? 

Thanks, Tim