Can someone assist me with determining the type of stock investment I sold last year?

This is a user to user forum and nobody here can see your income tax return nor your computer screen.  Accordingly, you need to provide some information before anybody can make a stab at answering your question. 

What what exactly are you referring to by "type of stock investment" here?  TurboTax, very broadly, has an interview for stocks that aren't acquired via some sort of employee stock compensation program and some specialty interviews for stocks that were acquired through these programs.  Maybe that's what you're referring to? 

But of course there are also interviews that deal with the "basis" of stock you're selling when you didn't simply buy the stock through a broker but instead it was gifted to you, you inherited it, and so forth.

Edit your message to provide some background information.