Read the following context and choose the best option to answer the question.
Context: If he fails to have enough concentration , he might produce an effect different from the desired one which can be potentially dangerous . The sole exception to this energy restriction are his wings which he can call forth at will without much problem . He is n't quite sure how they work , but extensive use is very taxing to his body .
Question: What may be the reason for not being sure how the wings work ?
Options: 
- The wings are new .
 - They did n't know they had them for a long time .
 - They were told they did n't have wings .
 - None of the above choices .


The wings are new .