Beagle犬有（）特性。

A.体形小，毛短

B.温驯易捕，亲近人

C.对环境适应力强，抗病力强

D.性成熟早，产仔多

For a light that has an intensity of 60 candies at its source, the intensity in candles, S, of the light at a point d feet from the source is given by the formula , where k is a constant. If the intensity of the light is 30 candles at a distance of 2 feet from the Source, What is the intensity of the light at a distance of 20 feet from the source ？（）

A.A

B.B

C.C

D.D

E.E