In a Field of Corn or Lettuce on a Farm

In a field of corn or lettuce on a farm, plants are cultivated with uniform spacing that will maximize plant growth. In natural habitats however, a uniform pattern of dispersion is much less common. While exceptions do exist, for example in populations of creosote bush in the desert, which of the following best explains why natural populations of plants usually exhibit clumped or random dispersion patterns?

A) Patterns of higher soil moisture, the concentration of soil nutrients, and the distribution of seeds from parent plants may be highly variable.
B) Precipitation across landscapes, especially mountain ranges, is uniform.
C) The competitive interactions between individuals of the same population usually lead to such dispersion patterns.
D) Since nearly all plants are wind-pollinated, the direction of breezes can affect whether plants will produce seeds.