How do animals contribute to soil productivity?

a. soil tramping

b. defecation

c. plant consumption

d. plant habitation

e. all of the above?

The correct answer is defecation.

Soil productivity is the capacity of a soil, in its normal environment, for producing a plant. A productive soil is a soil in which the chemical, physical, and biological conditions are favourable for plant growth. All organisms, including animals, contribute to the soil by adding organic matter and chemicals via their bodies (decomposition), excrement (through the urinary and digestive system) and food residues.