A Master Service Agreement (MSA) establishes the general terms and conditions for ongoing business engagements. This allows companies to reuse the same terms across multiple contracts, revisiting them periodically for updates. NDA (B) protects confidential information but does not define service terms. MOU (C) is a non-binding agreement, often used for partnerships, not formal service contracts. SLA (D) focuses on service performance expectations, not overall contract terms. Reference: CompTIA Security+ SY0-701 Official Study Guide, Security Program Management and Oversight domain.