(b) The correct match is as follows:
Summer Solstice- 21st June
Winter solstice- 22nd December
Vernal Equinox- 21st March
Autumnal Equinox- 23rd September June 21 is called the summer solstice in the Northern Hemisphere. In the Northern Hemisphere, the winter solstice occurs either December 21 or 22. Vernal Equinox is the time when the sun crosses the plane of the earth’s equator,making night and day of approximately equal length all over the earth and occurring about March 21. The Autumn Equinox is the first day of the autumn season and occurs when the sun passes the equator moving from the northern to the southern hemisphere. It occurs on 23 September.