The correct answer is option B.
Edmond Halley correctly predicted the return of the eponymous comet Halley after he realized several sightings of a comet were in fact the same comet.
By correctly understanding Sir Isaac Newton's law of gravity and also his ideas in mathematics, Halley was able to correctly predict that the comet that now bears his name would return periodically. He did this by discovering Halley's orbit in 1716 and thus being able to predict the year of its return.
The answer would the Columbian Exchange.
The North Atlantic Treaty Organization was created in 1949 by the United States, Canada, and several Western European nations to provide collective security against the Soviet Union. NATO was the first peacetime military alliance the United States entered into outside of the Western Hemisphere.
Supreme Headquarters Allied Expeditionary Force (SHAEF; /ˈʃeɪf/ SHAYF) was the headquarters of the Commander of Allied forces in north west Europe, from late 1943 until the end of World War II. U.S. General Dwight D. Eisenhower was in command of SHAEF throughout its existence.
