Double Account system is applicable to:

Consumer industries
Chemical industries
Public enterprises
Public utility concern

The correct answer is: D. Public utility concern.

A double account system is a system of accounting in which all transactions are recorded in two accounts, a debit and a credit. This system is used to ensure that all transactions are recorded accurately and that the financial statements are balanced.

Public utility concerns are businesses that provide essential services to the public, such as electricity, water, and gas. These businesses are often regulated by the government to ensure that they provide these services at a fair price.

A double account system is essential for public utility concerns because it allows them to track their income and expenses accurately. This information is important for making decisions about pricing, investment, and other matters.

The other options are incorrect because they are not businesses that provide essential services to the public. Consumer industries are businesses that produce goods for consumers, such as food, clothing, and electronics. Chemical industries are businesses that produce chemicals, such as fertilizers, plastics, and pharmaceuticals. Public enterprises are businesses that are owned and operated by the government.

I hope this helps! Let me know if you have any other questions.