Which of the following statements is true?

(A). According to AACR-2R the main entry is ‘the complete catalogue record of an item, presented in the form by which the entry is to be informally identified and cited. 

(B).  First level of description provides the maximun information

(C). The second level is a standard description which includes all the data which is necessary for description of documents 

(D). The third level provides information covering every descriptive element.