Pick out the wrong statement

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Pick out the wrong statement:

A. With change in temperature, the radiant energy emitted by a black body remains unchanged

B. Absorptivity of a body approaches unity in case of diffuse reflection

C. Absorptivity of a perfectly black body is unity

D. Value of Stefan-Boltzman constant is 4.876 × 10^-8 kcal/m².hr.°K⁴

Answer: Option A

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