To a perpendicular to the plane of ecliptic, the Earth's axis of rotation makes an angle of 23.5°. Had this angle been 0°, which one among the following would result?

• A. the length of day and night would have been the same all over the earth
• B. all of these
• C. three would have been no seasons
• D. the length of day and night would have been the same throughout the year