Which statement completes the SAS program to create the variable X with a value of Jameston?

The correct completion of the SAS program to create the variable X with a value of "Jameston" is achieved through the use of the PROPCASE function. This function is designed to convert the first letter of each word in the specified string (in this case, lname) to uppercase while transforming all other letters to lowercase, thus producing the title case format. This is particularly useful when formatting names, such as ensuring that "jameston" becomes "Jameston".

In context, the other available choices serve different purposes. UPCASE converts the entire string to uppercase, which would result in "JAMESTON". The uppercase function, while similar in name, does not exist in the conventional form as it is used in the context of the base SAS programming. Finally, the propercase function is not a recognized function in SAS. Thus, PROPCASE is the most suitable function to achieve the desired transformation for the variable X.