The counting rate observed from a radioactive source at $$t = 0$$ was 1600 counts s$$^{-1}$$, and $$t = 8$$ s, it was 100 counts s$$^{-1}$$. The counting rate observed as counts s$$^{-1}$$ at $$t = 6$$ s will be

A

250

B

400

C

300

D

200