Noon solar terms

Xi 'an is located in the north of the Tropic of Cancer, so in a year, the noon sun height is the highest in summer solstice, the lowest in winter solstice, and the noon sun height in vernal equinox and autumnal equinox is between the maximum and minimum, so it can be judged as ① summer solstice, ② vernal equinox and ③ winter solstice.

So choose: B.