In the SAS code provided, what effect does the CATX function have?

The CATX function in SAS is designed to concatenate multiple string values while using a specified character to act as a delimiter between those values. This means that when values are combined using CATX, the selected delimiter is placed between each of the concatenated values, ensuring they are clearly separated in the resulting string.

For example, if you use CATX with a space as the delimiter to concatenate the words "SAS", "Base", and "Programming", the result will be "SAS Base Programming". This functionality is particularly useful when you want to create readable strings from multiple variables or text elements.

The other choices reflect different characteristics of string concatenation that do not apply to the CATX function. It does not concatenate values without delimiters, does not specifically separate values by commas unless a comma is explicitly chosen as the delimiter, and it does not perform checks for missing values—those tasks would require different functions or additional logic in your code.