In mail merge operation which of the following might represent the main document?

• A sales brochure

• A form letter

• A database of Names and Addresses

• All of above

...
What are brochure and their purpose?
An informational paper document for advertising can be folded into a template, leaflet, or pamphlet. The purpose of brochures is to provide customers with detailed information about your company, products, services, etc. Also, Brochures can help you to increase the leads through a direct mail campaign. That is why in mail merge operation brochure represent the main part of the document in above given options.

Structure of Brochure: The main content of the brochure includes

1. the company name

2. its logo

3. an enlightening and relatable image

4. A small portion of detailed text.

Example of a Simple Brochure:

Image Source: Wikipedia