Part III Vocabulary (20 minutes)
Directions: There are 30 incomplete sentences in this part. For each sentence there are four choices marked A, B, C and D. Choose the ONE answer that best completes the sentence. Then mark the corresponding letter on the Answer Sheet with a single line through the centre. 【題組】51. Not having a good command of English can be a serious ________ preventing you from achieving your goals.
(A)) obstacle
(B)) fault
(C)) offense
(D)) distress