Comprehensive Explanation

The AEM GraphQL API is the recommended method for retrieving and delivering structured Content Fragment data to headless applications.

AEM Headless enables developers to separate content management from presentation. Content authors manage structured information using Content Fragment Models, while external applications retrieve the required content through API requests.

The AEM GraphQL API allows developers to select the exact fields and relationships required by a client application. This reduces unnecessary data transfer and supports efficient content delivery to websites, mobile applications, and other digital channels.

GraphQL queries can retrieve individual fragments, collections of fragments, and referenced content. AEM also supports persisted queries, which are particularly useful for production delivery and caching strategies.

Option A is primarily associated with rendering Content Fragments within AEM Sites pages through Core Components, rather than independently consuming structured content in a headless application.

Option B does not represent the standard headless content-delivery mechanism.

Option D refers to the Assets HTTP API. Although AEM provides asset-related and structured-content APIs, GraphQL is specifically designed for querying and delivering Content Fragment data to headless applications.

Therefore, option C provides the most appropriate architecture for the stated requirement.

Official Adobe Reference: Headless Content Delivery Using Content Fragments with GraphQL; Create an API Request — Headless Setup.