A developer needs to store variables to control the style and behavior of a Lightning...

For application configurations that control behavior and styling across different environments, Custom Metadata Types (Option A) are the industry-standard choice. The primary advantage of Custom Metadata over Custom Settings or Custom Objects is tha1t the2 records themselves are treated as metadata. This means they can be deployed using Change Sets, Salesforce CLI, or packages. When a developer moves code from a Sandbox to Production, the associated configuration records are included in the deployment, ensuring that the Lightning Web Component behaves identically in both environments without manual data setup.

Furthermore, Custom Metadata is highly "testable." In Apex unit tests, you can query Custom Metadata records without needing the (SeeAllData=true) annotation. If your component's Apex controller logic depends on these variables, the tests will remain robust and environment-independent. Custom Settings (Option C) and Custom Objects (Option B) store records as data, which cannot be deployed via Change Sets and require manual entry or data loading in every new sandbox or production org, increasing the risk of configuration errors. Custom Metadata provides the most "extendable" and deployable way to manage component-level constants and behavioral flags.