The correct option is A small quantity of quicklime or slaked lime solution
If the soil is acidic in nature, it not only decreases the solubility of minerals but also affects the availability of the nutrients. Thus, for converting the acidic soil into neutral soil, a small quantity of quicklime or slaked lime solution is added. Lime is alkaline in nature, which will neutralize the soil. While, iron sulphate, aluminium sulphate and peat are acidic in nature and can be used to reduce the alkalinity of the soil.