PT 65 S3 Q22

The passage offers which one of the following as anexplanation for why ... ...

The passage offers which one of the following as an explanation for why native plant varieties grew better when sown on land that had been out of production for 20 years than when sown on the plots enriched with soil taken from that land?
(A) Land that has been farmed for many years lacks certain key nutrients.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Dec 2011 LSAT (PT 65): Reading Comprehension