A. interesting
B. informal
C. brief
D. formal
✅ The correct answer is option B.
Business letters produce immediate effect because they are informal. A business letter is a letter written in formal language, usually used when writing from one business organization to another, or for correspondence between such organizations and their customers, clients and other external parties.
Business letters produce immediate effect because they are informal. A business letter is a letter written in formal language, usually used when writing from one business organization to another, or for correspondence between such organizations and their customers, clients and other external parties.