Which adjustments can be made using the query builder?

The correct answer highlights the functionality of the query builder, which is primarily designed to enhance data retrieval and reporting capabilities within the SAP system. By choosing the option that states "adding, removing, or customizing fields in queries," you recognize the core purpose of the query builder. This tool allows users to tailor queries to meet specific reporting needs, enabling them to select relevant fields that should be part of the output and to exclude those that are not necessary.

Query builders empower users to customize reports without extensive programming knowledge or dependency on IT support, making data analysis more accessible and efficient. This customization can involve adding new fields from the data sources, removing existing ones that do not contribute valuable insights, or modifying the structure of the query to reflect business requirements accurately.

In contrast, the other options do not align with the capabilities of the query builder. Adjusting system settings pertains to system administration and configuration tasks, which are unrelated to the function of querying data. Similarly, creating new user accounts is a user management function typically handled through system administration, while conducting system performance checks relates to monitoring and optimizing system efficiency, rather than data querying. Thus, the focus on query customization encapsulates the correct answer well.