Condensation is the answer. Hope that helps, happy holidays!
The part of the stem that gives rise to this pattern is : B. xylem
xylem is responsible in transporting water and nutrients. It die after a year or so and will leave the concentric pattern as it die
hope this helps
After gaining electron Chlorine becomes an <em><u>anion.</u></em>
<em><u>and </u></em><em><u>it's</u></em><em><u> </u></em><em><u>symbol</u></em><em><u> </u></em><em><u>is</u></em><em><u>. </u></em>

Hope it helps