The right option is; a. It is rich in minerals from volcanic deposits.
Volcanic soil (andisol) is a light and fluffy soil that is formed from volcanic ash and cinder deposits. Volcanic soil is very fertile because it is highly composed of non-crystalline minerals, such as allophane and imogolite from volcanic deposits. These minerals create strong bonds with organic matter which leads to the accumulation of organic matter in the soil. Volcanic soil has high water retention capability and it supports the growth of crops such as rice, maize and fruits.