It could've ended much earlier but it became a competition between the USA and the Soviet Union to see who was/ could be the strongest and most powerful country. it also contributed to the 'race to space' between the two.
The Answer is B hope it helps you
They thought there were chemical weapons
Over 200 years. After the First Crusade (ending in 1099) the Crusades lasted off and on for over 200 years. All of the crusades were unsuccessful except for the first, but after the third (with Richard Lionheart) negotiations allowed unarmed Christians to enter the holy city.