Which of the following is NOT true about linguistic dictionaries?

Which of the following is NOT true about linguistic dictionaries?

A.They aim at defining words and explaining their usages in the language.

B.They usually cover such areas as spelling, pronunciation, meaning, grammatical function, usage and etymology, etc．

C.They can be monolingual and bilingual.

D.They provide encyclopaedic information concerning each headword．

正确答案是D