To answer this question, we need to understand the roles of each component in the Informatica PowerCenter architecture.
Option A) Mapping Designer - This option is incorrect because Mapping Designer is a client tool used to design and create mappings in PowerCenter. It connects to the Repository server to store and retrieve mapping metadata.
Option B) Informatica server - This option is incorrect because the Informatica server, also known as the Integration Service, is responsible for executing the workflows and tasks defined in the mappings. It connects to the Repository server to retrieve the necessary metadata and configuration information.
Option C) PMREP command - This option is incorrect because the PMREP command is a command-line utility provided by Informatica to manage and administer the Repository server. It can be used to perform various tasks like importing and exporting repository objects, creating backups, managing privileges, etc. It interacts with the Repository server to perform these operations.
Option D) Repository agent - This option is correct because there is no component called Repository agent in the Informatica PowerCenter architecture. The Repository server is responsible for managing and storing the metadata of all the PowerCenter objects. The Repository agent does not exist.
Therefore, the correct answer is D) Repository agent.