Assigning Missing Values to Unsatisfactory Responses May Be Desirable in All

Assigning missing values to unsatisfactory responses may be desirable in all of the following situations EXCEPT:

A) if the number of responses is small.
B) if the proportion of unsatisfactory responses for each of these respondents is small.
C) if the variables with unsatisfactory responses are not key variables.
D) A and C
E) All of the mentioned situations (A, B and C) qualify for the assignment of missing values when unsatisfactory responses are discovered on a questionnaire.