Which circle of latitude is positioned exactly under the Sun during the equinox?

Which circle of latitude is positioned exactly under the Sun during the equinox?

A Equator
B Tropic of Cancer
C Arctic Circle

The Equator separates the Earth into the Northern and Southern Hemispheres and is an equal distance from the North and South Poles. The equatorial circumference of the Earth is over 40,000 kilometres.

The correct answer is Equator.