Statistical Analysis System (SAS) Programming Certification 2025 – 400 Free Practice Questions to Pass the Exam

The correct option creates a subset of the data by leveraging functions that allow for case-insensitivity when searching for the string "walnut" within the Finish variable. Specifically, the use of the `lowcase` function converts the contents of the Finish variable to lowercase, which enables a straightforward comparison against a lowercase string representation of "walnut."

By applying `lowcase(finish)`, the function standardizes the case of the Finish variable, thereby ensuring that any variation of "walnut" (such as "Walnut", "WALNUT", etc.) will match successfully, as they will all be converted to "walnut" for the comparison. The `index` function then checks if "walnut" exists within this modified string. A result greater than 0 indicates the substring is present, effectively filtering the data to only those entries that contain "walnut," regardless of their original casing.

This method is robust in its case-insensitivity and thus accurately fulfills the requirement stated in the question.