The policies of this subpart shall apply to the following procurement instruments, to include amendments, modifications, and change orders thereto:

(a) Solicitations.

(b) Contracts, including, but not limited to, Governmentwide acquisition contracts (GWACs), multi-agency contracts (MACs), Federal Supply Schedule (FSS) contracts, indefinite-delivery contracts, and purchase orders.

(c) Agreements that include pre-priced supplies or services.

(d) Task and delivery orders.