Among the Reasons for the Frequent Use of Composite Measures

Among the reasons for the frequent use of composite measures is(are) that:

A) the researcher is seldom able to develop in advance single indicators of complex concepts.
B) a single data item might not have enough categories to provide a range of variation.
C) composite measures give a more comprehensive and accurate indication of a given variable.
D) they are efficient data reduction devices.
E) all of these choices.