Which of the following would not be considered an advantage of using an internal control questionnaire in understanding and documenting the controls in an important accounting application? Questionnaires can be: 

a. Computerized to provide linkages of weaknesses to particular types of errors that might occur in the account balances. 

b. Used for many years without updating.

c. Easily understood and provide easy identification of potential control deficiencies through "no" responses to questions.

d. Adapted to both large and small businesses as well as to different industries.