49. According to the passage, what impacts have world events had on life expectancy?
(A) They have shortened life expectancy.
(B) They have lengthened life expectancy.
(C) They have made life expectancy rise smoothly.
(D) They have had no significant effect on life expectancy.

答案：登入後查看
統計： A(27), B(136), C(107), D(155), E(0) #717765

Cassidy Tung

B1 · 2015/01/28

#981842

Viewed globally, the lengthening of life spans seems independent of any single, specific event.

從全球來看，延長壽命似乎獨立於任何單一具體的事件。