The skin is the largest organ of your body ______of three layers; ______are essential to ____your bo

题目简介

The skin is the largest organ of your body ______of three layers; ______are essential to ____your bo

题目详情

The skin is the largest organ of your body ______of three layers; ______are essential to ____your body  against diseases, poisons and the sun's harmful rays or radiations.     
[     ]

A. consisting; they; protecting                  
B. consisting; which; protecting     
C. made up of; they; protect                    
D. consisted; they; protecting

题型:单选题难度:中档来源:同步题

答案

A

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