What is the term for the situation when an owner receives a single bid from each contractor for a project?

The term for the situation when an owner receives a single bid from each contractor for a project is known as a "Base Bid." In this context, a base bid represents the basic cost estimate for the construction project, encompassing the minimum contract price provided by contractors based on the specified scope of work. When only one bid is received, it signifies a lack of competitive pricing, which can affect the owner’s ability to assess the fairness of the proposed cost against prevailing market rates.

Other terms offered in the choices refer to different aspects of construction projects or bidding processes. An alternate bid usually refers to additional proposals that might change the scope or materials used in the base project. Design development is a phase in the design process where plans are refined before final documentation. Close-out refers to the finalization of a project upon completion, including the settlement of all contractual obligations and final inspections. Thus, while these terms are relevant to construction projects, they do not capture the specific scenario described in the question pertaining to single bids.