The answer is either A or D
I don’t know why they make everyone type more than 20 characters but B sounds like the most reasonable answer.
<em>Highlighted </em><em>muscles </em><em>are </em><em>the </em><em>muscles </em><em>of </em><em>the </em><em>neck. </em><em>It </em><em>is </em><em>a </em><em>group </em><em>of </em><em>four </em><em>muscles </em><em>which </em><em>helps </em><em>to </em><em>stabilize </em><em>the </em><em>shoulder </em><em>joint. </em>
<span>1. temperature
2.water purification
3. succession
4. alien species
5. conduct a survey of a species population in an ecosystem
6. adopt ecological conservation practices</span>