In a day, the lowest temperature on land generally appears at () a. Before and after sunrise b. At noon12; C. After noon (about 1 4) D. At noon1.

The change of temperature in a day is the daily change of temperature. Generally speaking, the highest temperature in a day on land appears around 14, and the lowest temperature appears around sunrise. During the day, solar radiation reaches its maximum at noon 12. At this time, the ground temperature rises with the absorption of solar radiation, and the ground radiation gradually increases. 13 or so, the ground temperature reaches. This is the moment when the surface heat changes from excess to loss. Because it takes some time to transfer heat to the atmosphere after the surface temperature rises, the highest temperature in a day appears around 14, which is the moment when the atmospheric heat turns from excess to loss. After 14, the solar radiation continued to weaken, the ground temperature continued to decrease, and the temperature also decreased, reaching the lowest value around sunrise.

So choose: a.