Step 1: Understanding prescriptive rules.
Prescriptive rules are concerned with prescribing how language ought to be used rather than describing how it is actually used by speakers.
Step 2: Focus on written standards.
Such rules typically arise in grammars, style guides, and educational contexts, where they set norms for correctness, especially in written language.
Step 3: Elimination of incorrect options.
Option (B) refers to theoretical linguistics and universal grammar, which is descriptive, not prescriptive.
Option (C) deals with dialectology, which describes variation rather than prescribing norms.
Option (D) concerns language change, a domain of descriptive linguistics.
Step 4: Conclusion.
Therefore, prescriptive rules primarily provide criteria for written language.