December is the month in a year.A. twentyB. twelveC. twentiethD. twelfth

问题补充：

December is the month in a year.

A. twenty

B. twelve

C. twentieth

D. twelfth

答案：

A. twenty

B. twelve

C. twentieth

(答案→)D. twelfth

解析：根据前文定冠词the可知填序数词twelfth，选项C是twenty 20的序数词形式，故选D。