The primary legal requirement for a legal description in a real estate contract is to satisfy the Statute of Frauds, which mandates that contracts for the sale of land must be in writing and contain a description of the property sufficient to identify it with reasonable certainty. This unique identification distinguishes the specific parcel from all others, ensuring the contract is legally enforceable and that a clear, marketable title can be conveyed. While a street address may be used for convenience, it is not legally sufficient because it can change or be ambiguous. The legal description provides a permanent and precise identifier.

A. Property taxes are calculated using the property's assessed value and a tax identification number, not directly from the legal description.

C. While the legal description defines the boundaries, its primary purpose is unique identification for conveyance, not the regulation of future construction, which is governed by zoning and building codes.

D. This is a beneficial outcome of a proper legal description, but the fundamental legal reason is the need for unique identification (B) to create a valid and enforceable contract.

1. Maryland Code, Real Property Article, § 5-103. This section of the Maryland Code codifies the Statute of Frauds for real estate, stating that no action may be brought on a contract for the sale of real property unless it is in writing and signed. Case law interpreting this statute has consistently held that the writing must include a description of the property sufficient to identify it.

2. University of Maryland, Agricultural Law Education Initiative. In the publication "Understanding Agricultural Contracts," it is noted, "A sufficient description of the land is also required. The description of the land must be clear enough for the land to be identified." This underscores the primary purpose of identification. (Source: "Understanding Agricultural Contracts," ALEI, University of Maryland Francis King Carey School of Law).

3. Gaudio, A. J., et al. (2019). The American Law of Real Property. As a standard academic treatise on property law used in university courses, this source explains that for a deed or contract to be valid, the description of the land "must be sufficiently definite and certain to enable the land to be identified." (Chapter on "The Formalities of a Deed"). This principle is foundational to real estate law nationwide, including Maryland.