Which of these strategies ensures soil quality for the next growing season?

digging irrigation canals
using crop rotation
enclosing animals in fences
finding new sources of seeds

i believe it d) heterogeneous

(202 bc - 220 ad) dynasty started by lui bang; a great and long-lasting rule, it discarded the harsh policies of the qin dynasty and adopted confucian principles; han rulers chose officials who passed the civil service exams rather than birth; it was a time of prosperity

it affected it because the kingdoms (with trade) slowly got richer and richer.