Agriculture did not emerge until the end of the second ice age. Today, pastoral nomadism or livestock farming are practiced in semiarid areas, in contrast with plantations or intensive subsistence rice farming, which are practiced in subtropical ones. These facts exemplify
A.
the relationship between agricultural regions and bioclimatic conditions.
B.
the biodiversity of natural species of plants and animals.
C.
the importance of the ice ages to the nutrient level of soils worldwide.
D.
the effects of culture and tradition on food preferences and food production.
E.
the diffusion patterns from agricultural hearths.