The survey shows that we are enjoying less and less good sleep, rates of heart diseases have risen rapidly．
A. while
B. although
C. if only
D. as though
网友回答
(答案→)A. while
B. although
C. if only
D. as though
解析：句意：调查显示当我们正在享受着越来越少的好睡眠时，心脏病的发病率却迅速地上升。A. while当…的时候；和…同时；B. although尽管，虽然； C. if only 只要，要是……多好；D. as though仿佛，好像；由句意可知选A。
考点: 考查连词和代词的用法。