Which of the following statements is true/correct

Options

A. During clear nights, the temperature rises steadily upward near the ground level
B. Newton's law of cooling, an approximate form of Stefan's law, is valid only for natural convection
C. The total energy emitted by a black body per unit time per unit area is proportional to the square of its temperature in the Kelvin scale
D. Two spheres of the same material have radii 1m and 4m and temperatures 4000 K and 2000 K respectively. The energy radiated per second by the first sphere is greater than that radiated per second by the second sphere

Answer

B