GRE General Test: TC-573346 GRE Text Completion

Cultivation of a single crop on a given tract of land leads eventually to decreased yields, this can be (i)_____by crop rotation, denying the pathogens a suitable host for a period of time. However, even if crops are not rotated, the severity of diseases often (ii)_____after a number of years as the microbial population of the soil changes and the soil becomes “(iii)_____” to those diseases.
Blank (i)
Blank (ii)
Blank (iii)