Which Statement Is True If Deciding on the Number of Scale

Which statement is true if deciding on the number of scale categories to use in a non-comparative itemized rating scale?

A) If the respondents are interested in the scaling task and are knowledgeable about the objects,a larger number of categories may be employed.
B) If telephone interviews are involved,many categories may confuse the respondents.
C) Space limitations may restrict the number of categories in mail questionnaires.
D) All of the statement above are true.