Correct option is B
Electrolysis is an example of a reversible process. In electrolysis, electrical energy is used to drive a chemical reaction, such as the decomposition of water into hydrogen and oxygen. This process can be reversed by using the products (hydrogen and oxygen) in a fuel cell to produce water and generate electricity, making it a reversible reaction under ideal conditions.
In contrast:
Heat transfer often involves irreversible processes due to entropy increase.
Combustion is a highly irreversible process as it involves the complete conversion of fuel to energy and products.
Plastic deformation is irreversible because it results in a permanent change in the material's shape.
