What does soil structure refer to?
a. how the soil particles clump together
b. parent material
c. mineral content
d. amount of organic matter present.

A. How the soil particles clump together

Explanation:

Solid part of the soil clumps together. There are air pores between the soil particles. This determines the soil structure. The soil takes the shape based on the its physical and chemical properties. The main four types of soil structure are:  

1. Columns

2. Blocky

3. Granular

4. Plate-like

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