People often think they are energetic and healthy and don’t need exercise. , I have to warn that it is pletely wrong.
A. However
B. Therefore
C. Otherwise
D. Meanwhile
网友回答
(答案→)A. However
B. Therefore
C. Otherwise
D. Meanwhile
解析：A然而；B因此；C否则，要不然；D与此同时；句意：人们经常认为自己精力充沛很健康，不需要锻炼，然而，我不得不警告这是完全错误的。根据句意可知A项表示上下文的转折关系。故A正确。