<span>D. It was an ecological transformation.</span>
Columbian Exchange was the introduction of Old World plants and animals into the New World and the other way. An example of this was the introduction of tomatoes and potatoes to Europe.
This <span> attack was directed against trains passing through Kasumigaseki and Nagatacho, home to the Japanese government.
Hope this helps!</span>
Trenches were common throughout the Western Front. Long, narrow trenches dug into the ground at the front, usually by the infantry soldiers who would occupy them for weeks at a time, were designed to protect World War I troops from machine-gun fire and artillery attack from the air.