Any good garden compost may appropriately be used for soil drainage and ... ...

Any good garden compost may appropriately be used for soil drainage and fertility. The best compost is 40 to 60 percent organic matter and is dark brown in color. However, compost that emits a strong ammonia smell should not be used for drainage and fertility, for that smell means that the organic matter has not sufficiently decomposed. Which one of the following is most strongly supported by the information above?
(A) Compost that is 80 percent organic matter has probably not decomposed sufficiently.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Oct 2012 LSAT (PT67): Logical Reasoning B