The weather forecast host intercepted

During the day, compared with land, water with the same quality absorbs the same heat, and the temperature of water rises less, while the temperature of sandy soil rises more; At night, when the same heat is released, the temperature of water drops less, and the temperature of sand and gravel soil drops much, so the daily temperature difference in inland areas is larger than that in coastal areas. According to the temperature difference between the two places, A is inland and B is coastal.

So, the answer is: b; Coastal areas are rich in water, with large specific heat capacity and small temperature change.