What kind of economy is being described : Companies
decide what to make based on demand.

That is called Supply and Demand. The company and customers have a relationship where the customer wants a product and the company supplies it. :)

Explanation:

"The following statements are applicable to the controlling idea of a text:

1. IT INCLUDES THE TOPIC OF THE TEXT.

2. IT INCLUDES THE AUTHOR'S VIEWPOINTS.

3. IT IS THE UNDERLYING MESSAGE OF THE TEXT.

4. IT IS COMPARABLE TO THE THEME FOR A WORK OF FICTION.

In essay writing, controlling idea refers to the main idea in the essay and it identifies the author's purpose in writing a particular essay or text. The controlling idea of a text is made up of an author's opinion about a particular topic. Generally, the controlling idea of a text provides a kind of framework from which readers can interpret the message that a text present."