The following is about the "summer solstice" among the 24 solar terms in the northern hemisphere.

Answer analysis: this question belongs to geographical common sense. "Summer solstice" is one of the 24 solar terms. On June 2 1 or 22 (the second half of the fifth month of the lunar calendar) every year, when the sun reaches 90 degrees of the yellow meridian, item A is correct. On the solstice in summer, the direct sunlight on the ground reaches the northernmost point of the year and almost directly reaches the Tropic of Cancer. At this time, the day in the northern hemisphere is the longest, and the farther north it is, the longer it is. The ancient book "Twenty-four solar terms" said: "As soon as the anode arrived, Yin Qi began to grow. In the north, the days are long and the shadows are short, so it is called the summer solstice. " Item b is correct. "Summer Solstice" is a season reflecting seasonal changes, which indicates the coming of hot summer, not summer. Item c is wrong. The seasons in the northern and southern hemispheres are just the opposite. It is summer in the northern hemisphere and winter in the southern hemisphere. Item d is correct. So the answer is C.