Once you have determined the main ideas of your sources, see how they relate to one another. look for similarities and differences. look for ideas from one that add to your understanding of another. choose the connection below you can make among the three sources.

Correct answer is: "He had witnessed during his World War II service."

Explanation:

Jarrell was an American poet,  translator, editor, critic, and novelist , called as "the most heartbreaking" by Robert Loweland.

His first original poems  originate from his experience in the Air Force, where he showed the grim highlights of the wastefulness of war.