Among Extensive Cultivators,one of the Key Factors That Determines Whether

Among extensive cultivators,one of the key factors that determines whether land will be considered exclusive and defended is:

A) Contact with Western cultures (societies that have Western contact defend,others do not) .
B) The types of crops planted (lands where tree crops are planted are defended but root crops are not) .
C) The presence of irrigation works (lands with such works are defended,others are not) .
D) The presence of warrior societies (cultures with warrior societies defend lands,others do not) .
E) The relationship of land and population (societies with high population density defend lands,others do not) .