I am pretty sure that <span>the option which best describes one of the themes in "mending wall" by Robert frost is being shown in the first represented variant:
</span><span>wall" by Robert frost?
a.people often put up barriers</span><span>
During the poem author always asks : </span> "where it is we do not need the wall"? and the answer he gets is that "Good fences make good neighbors'', he was wondering why people always create barriers or obstacles in their lives so I bet this option is the most suitable one.
I would think D and B!
Hope that helps a little
