Application Programming Interfaces (APIs) are the best choice for allowing a developer to programmatically interact with a database from within a custom application. APIs provide a set of routines, protocols, and tools for building software and applications and are designed to facilitate the creation, reading, updating, and deletion of data. Direct access often involves manually entering data through a client or command-line interface, which is not automated. Import/export utilities are generally used for bulk data operations rather than interactive, application-driven access. SQL injection is a technique used by attackers to insert malicious SQL code into a database query and is not a legitimate method of database interaction.