A proposal is a statement or suggestion referring to a proposed action. Usage is qualified by a noun, unless the sense of use refers to an unspecified or undecided situation. The qualified term is then described as 'the proposal', with the qualifier taken as given by prior reference. (Repetition of a term like 'business proposal' would be redundant.) The term can also be used as an abstract referring to a generic subject.
Examples of Proposal:
After prior qualification: The business proposal from ABCDE is the best. That proposal meets all our needs.
Abstract: Any proposal must contain technical specifications.https://facstaff.gpc.edu/~ebrown/infobr3.htm