What is the primary law governing the protection of buyers purchasing subdivision lots and condominium units?

The correct choice is the Maceda Law, which serves as the primary legal framework for protecting buyers in the purchase of subdivision lots and condominium units. This law, officially known as Republic Act No. 6552, aims to safeguard the rights of buyers and provides them with specific guarantees when dealing with real estate transactions.

Under the Maceda Law, it is established that buyers have the right to a refund of their payments should they choose to cancel their purchase after fulfilling certain conditions. It also mandates developers to provide buyers with clear information regarding the terms of their agreements, helping to ensure transparency. Additionally, the law enhances consumer protection by requiring developers to comply with regulations concerning the quality and administration of properties, thus fortifying the buyers' interests in the real estate market.

In contrast, the other options mentioned are either governing bodies or authorities involved in housing and land development but do not specifically serve as the overarching law that provides direct protections to buyers in residential transactions. For example, the National Housing Authority focuses more on housing projects and programs, while the Housing and Land Use Regulatory Board oversees compliance with real estate laws and regulations. The Subdivision and Housing Development Association is more of an industry body rather than a law designed to protect buyers.