To remove unwanted observations from a data set in RapidMiner, use the _______ operator.

• A. Select Attributes
• B. Filter Examples
• C. Transform Data
• D. Sort

Answer: (B)

Removing unwanted observations means keeping only the rows that meet a given condition. In RapidMiner, that is done with the Filter Examples operator. It evaluates a boolean condition for each example (row) and either keeps or drops that example based on how you configure it. This lets you remove outliers, exclude irrelevant subgroups, or drop missing or undesired cases by specifying criteria like a threshold on an attribute or a specific class value.

Other operators operate on different parts of the data: Select Attributes changes which features (columns) are present, Transform Data applies calculations or modifications to values, and Sort only rearranges the order of the examples without removing any.