Which of these world war ii events happened last? a battle of britain b d-day invasion c invasion of poland d dropping of the atomic bomb on hiroshima?

Dropping the atomic bomb on Hiroshima

Here's the chronological order:

Invasion of Poland - September, 1939 (beginning of World War II in Europe)

Battle of Britain - July thru October, 1940

D-Day invasion - June, 1944

Dropping of atomic bombs on Hiroshima and Nagasaki  - August, 1945

The use of atomic bombs was the final devastating act of destruction of the Second World War.