sorry I somehow thought it was a choice of 1, 2, or 3... reading in haste.  usually the cash-crop scenario involves the works:  peasant farmers are displaced from the good lands and forced to work very marginal soils;  monocrops encourage epidemic blights and pest population booms;  hacienda monocropping reduces soil fertility rendering even "good" lands exhausted and unproductive.  and so on.

The difference between theory and practise in practise ...