The spread of roots around a plant is usually greater than the depth of the roots is a completely false statement. It totally depends on the type of plant in regards to the type of root it will have. Normally there are two kinds of roots and they are taproot and fibrous roots. In case of taproots the main root goes downwards and smaller roots branches out of it. In case of taproots, it is true that the spread of roots is smaller than the depth of the roots. In case of fibrous roots, the spread of roots is greater than that of the depth of the roots. A wig tree is an example of a plant having taproot. in the wig tree the root can go to a depth of around 120 meters.
The answer is A. because mechanical weathering increases the surface that can be attacked by chemical weathering.
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