The solar terms with the same length of day and night in the northern and southern hemispheres are () A. Before and after vernal equinox and summer solstice B. Before and after vernal equinox and autu

The solar terms with the same length of day and night in the northern and southern hemispheres are () A. Before and after vernal equinox and summer solstice B. Before and after vernal equinox and autumn equinox C. Before and after summer equinox and autumn equinox D. The constant rotation of the earth around the sun is called the revolution of the earth. The direction of the revolution is from west to east, and the cycle is one year. When the earth revolves around the sun, the direct sunlight point moves regularly between the tropic of cancer in a year. When the sun shines directly on the equator, it is the vernal equinox or autumnal equinox in the northern hemisphere, which is divided equally between day and night.

Therefore, choose: B.