問題詳情
38 The invention of the light bulb was a major ______in human history because this invention allows for longer productive hours and improved quality of life at night.
(A) hardship
(B) dispute
(C) milestone
(D) bargain
參考答案
答案：C
統計：A:0,B:0,C:1,D:0,E:0
難度：計算中