Final answer:
You would select the F3 function button to inquire on a client using their SSN. The correct option is C.
Step-by-step explanation:
To inquire on a client using their SSN, you would select the F3 function button. The F3 function button is commonly used as a shortcut for searching or querying information in computer systems.
In this case, selecting F3 would likely prompt a search interface where you can input the client's SSN to retrieve their information.
For example, if you are using a software application or a database management system, pressing F3 might bring up a search box where you can enter the client's SSN and immediately see their details.
Hence, the correct option is C.