问题详情

Directions: There are 15 incomplete sentences in this section. For each sentence there are four choices marked A, B, C and D. Choose one answer that best completes the sentence and blacken the corresponding letter on the answer sheet.
6. ______ the look on his face, he wasn"t satisfied with their performance.
A. To judge by
B. Judging by
C. Judge by
D. To be judged by 请帮忙给出正确答案和分析，谢谢！