Consider the following statements:Statement I: In January, in the Northern Hemisphere, the isotherms bend equatorward while crossing the landmasses, and poleward while crossing the oceans.Statement II: In January, the air over the oceans is warmer than that over the landmasses in the Northern Hemisphere.Which one of the following is correct in respect of the above statements?

1. A

   Both Statement I and Statement II are correct and Statement II explains Statement I

   Both I and II are correct and II explains I. In January, northern continents are colder than oceans, so isotherms bend equatorward over land and poleward over oceans.

2. B

   Both Statement I and Statement II are correct but Statement II does not explain Statement I

   Both correct but II does not explain I. The temperature contrast is exactly why the isotherms kink.

3. C

   Statement I is correct but Statement II is not correct

   I correct, II not. Oceans are milder than land in northern winter.

4. D

   Statement I is not correct but Statement II is correct

   I not, II correct. The atlas pattern in I holds.

Summary. Official Set A key is (a). In January the northern landmasses are very cold and the oceans relatively warm (II). Therefore January isotherms dip south over continents and bulge north over oceans (I). II is the physical reason for I. That is both correct, and II explains I.