Concept:An equinox is the moment when the Earth’s equator passes exactly through the centre of the Sun’s disk. On this day, direct rays of the Sun fall on the equator, causing nearly equal day and night across the globe.Explanation:Earth’s tilted axis and its revolution around the Sun create changing seasons. Twice a year, the Sun is exactly above the equator. These are the spring equinox (around March 20) and the autumnal equinox (around September 22). On these dates, the Sun’s rays strike the equator most directly. As a result, both the Northern and Southern Hemispheres receive the same amount of sunlight. Day and night are almost equal in length everywhere. In contrast, the Tropic of Cancer and Tropic of Capricorn receive direct rays only on solstices. The Arctic Circle never gets direct rays. Therefore, on an equinox, only the equator experiences the Sun directly overhead.Answer:B. Equator