In conservation plowing, why are dead weeds and stalks of the previous year s crop left in the ground?
a. to keep the soil from becoming too fertile
b. to reduce the amount of seed needed for the next year s crop
c. to retain moisture and hold the soil in place
d. to keep more organisms out of the soil

c. to retain moisture and hold the soil in place

Explanation:

Conservation plowing is a sustainable practice which is done to retain the quality of the soil for the future agricultural activity. In this the stalks and weeds of the previous crops are left during the process of harvesting of the crop. This will prevent the erosion of the soil as the stalks and weeds will hold the soil and retain it's moisture content as this will not allow the direct exposure of soil to external environment for evaporation.