The correct answer is option 'A', the lost-wax process.

The lost-wax process, also known as cire perdue, is a metal-making technique that has been used in several regions of India for centuries. This intricate and ancient process involves creating a metal object by pouring molten metal into a wax model, which is then melted away or lost to create a hollow mold. The molten metal takes the shape of the wax model and solidifies, resulting in a detailed and accurate final product.

The lost-wax process has been practiced in various regions of India, including the states of Maharashtra, Tamil Nadu, and West Bengal. It is particularly renowned for its use in the production of bronze sculptures, which are highly valued in Indian art and culture.

Here is a breakdown of the lost-wax process:

1. Creation of a wax model: Skilled artisans create a detailed wax model of the desired object. This model captures all the intricate details and features of the final product.

2. Wax model assembly: The wax model is then attached to a wax sprue, which serves as a channel for the molten metal to flow into the mold. Several wax models can be attached to a single sprue, forming a cluster.

3. Investment: The wax model cluster is coated with a mixture of fine clay, sand, and other refractory materials known as the investment. This investment is applied in layers to create a mold that can withstand the high temperatures of the molten metal.

4. Dewaxing: The investment mold is heated to melt and remove the wax, leaving behind a hollow cavity in the shape of the original wax model. This step gives the process its name, as the wax is lost or melted away.

5. Preheating and pouring: The investment mold is further heated to remove any remaining moisture and preheat the mold. Once hot enough, the molten metal is poured into the mold through the sprue.

6. Cooling and solidification: The mold containing the molten metal is allowed to cool and the metal solidifies, taking the shape of the original wax model.

7. Finishing: Once cooled, the investment mold is broken away, revealing the metal object. The object is then cleaned, polished, and finished by skilled craftspeople to enhance its appearance.

The lost-wax process is a labor-intensive and time-consuming technique that requires a high level of skill and craftsmanship. It has been passed down through generations of artisans in India and continues to be a significant part of the country's rich artistic heritage.