According to the latest research, getting enough sleep is to maintaining good health and reducing stress.
A. practical
B. contradictory
C. essential
D. alternative
网友回答
A. practical
B. contradictory
(答案→)C. essential
D. alternative
解析：句意：根据最新的研究，充足的睡眠是维持良好的身体健康和减少应力的根本所在。A. practical实用的；B. contradictory矛盾的；C. essential基本的；D. alternative可替代的。故选C。
考点: 考查形容词的用法。