The supply of land for agricultural purpose can be increased through _______

Analyze the question: It asks how the supply of land for agricultural purposes can be increased. Land is generally fixed in total supply (a "gift of nature"), but the amount available for a particular use, such as farming, can be expanded.

Concept: Land has a fixed supply in the aggregate, but it can be increased in practical terms through:

• Reclamation: turning swamps, marshes, or coastal and flooded areas into usable land.
• Irrigation: making dry or arid land fit for crop cultivation.
• Clearing forests or bush for farming.

Examining each option:

• A. Mechanized farming: This improves productivity (output per hectare) and the efficiency of land use. It does not add any new land, so the supply of land is unchanged.
• B. Reclamation and irrigation: Reclamation creates new land from water or swamp, and irrigation turns barren or dry land into arable land. Both increase the actual area available for farming. Correct.
• C. Increase in the price of land: A higher price may raise the quantity supplied to the market (as owners sell more), but it does not create more physical land. Land supply is largely perfectly inelastic.
• D. Converting building sites to farmland: This only shifts land from one use to another. It increases land for agriculture at the expense of housing, so total land is not increased. It is a reallocation, not a true increase.

Answer: The correct option is **B.

Exam tip: Remember "land is fixed, but usable land can grow." Whenever you see a question on increasing land supply, look for the words reclamation, irrigation, or drainage. Options about productivity (mechanization, fertilizers) improve efficiency, not quantity.