Which of the following is NOT a desk dictionary?

Which of the following is NOT a desk dictionary?
A、The Word Book Dictionary
B、The Concise Oxford Dictionary,Ninth Edition
C、Oxford Advanced Learner's Dictionary,3rd Edition
D、Webster's New World Dictionary,2nd College Edition
【正确答案】：A
【题目解析】：《单词书词典》不是案头词典。