Which of the following is true about the PAGEBY statement?

The PAGEBY statement is designed to manage how output is organized in relation to grouped data, specifically in procedures like PROC PRINT and PROC REPORT. When using PAGEBY, the statement instructs SAS to print each observation group on a separate page. This can enhance the readability of reports by clearly separating different groups, providing a clean division that can be helpful for review and analysis. Each subgroup is neatly delineated, making it easier for users to interpret the results of different segments of the data.

The other options do not accurately reflect the functionality of PAGEBY. For instance, suppressing printed output would not align with the purpose of this statement, as its primary role is to enhance output organization rather than suppress it. Additionally, while merging datasets is a common task in data manipulation, the PAGEBY statement does not facilitate this action. Lastly, rearranging observations in descending order pertains to sorting data rather than controlling how grouped outputs are presented. Thus, the true nature of the PAGEBY statement is clearly captured in the assertion that it separates each subgroup onto its own page during output generation.