The correct answer is: a) Pasture and fodder.
Pasture and fodder are the most common type of feed used for livestock in Assam. Pasture is land that is used to grow grass and other plants that livestock can eat. Fodder is any plant material that is used to feed livestock, such as hay, silage, and green chop.
Commercial feed is a type of feed that is made from a variety of ingredients, such as corn, soybeans, and wheat. It is often fortified with vitamins and minerals.
Agricultural byproducts are materials that are left over from the production of crops or other agricultural products. They can be used to feed livestock, but they may not be as nutritious as pasture or fodder.
Processed grains are grains that have been processed in some way, such as by milling or grinding. They can be used to feed livestock, but they may not be as nutritious as whole grains.
In conclusion, the most common type of feed used for livestock in Assam is pasture and fodder. Pasture is land that is used to grow grass and other plants that livestock can eat. Fodder is any plant material that is used to feed livestock, such as hay, silage, and green chop.