The list of illustrations in a formal proposal, specifically mentioning the page numbers associated with each graphic, primarily serves the purpose of: C. It tells them where to find graphics that support the text.
What is it about?
This list guides readers to the pages where they can locate the production output graphics for each plant, providing visual support and complementing the textual information in the proposal.
In a formal proposal, especially one with complex information or data, it's common to include visual aids like charts or graphs to help convey information more effectively. The list of illustrations you provided includes the titles of these graphics along with the corresponding page numbers.