Final answer:
The type of letter from a business to another about business matters is a Business letter, which is formal and follows a specific format.
Step-by-step explanation:
The type of letter that is sent from one business to another about business matters is known as a c) Business letter.
A business letter is used for formal correspondence between businesses, institutions, or politicians.
It is professional in tone, follows a specific format, and conveys a clear purpose.
Effective business writing should be clear, concise, and direct.
The format typically includes the sender's address, recipient's address, date, a salutation, body paragraphs that explain the purpose and include supporting details, and a formal closing.