Elbow, Closet Elbow, or Long Turn Elbow for closet flange connection

Which fitting would you usually use in order to connect a closet flange? My main DWV pipe is 3". I am trying to figure out which elbow to use.

Also, can I use a Sanitary Tee w/90° Right Inlet (All Hub) to connect the toilet drain as well as a bathtub drain to it? In this case I would not have to run a seperate vent for the tub drain. If I can lower the San Tee enough I could probably be able to connect the tub drain to it and still having enough slope for both drains. Would this work and still be up to code?

Thanks for your help,

depends on the space you have to work in, any of the above are good. As for the san tee, absolutely not, no way, no how. You can use a side outlet elbow but not a heel either high or low pattern

Tom, this is the San Tee fitting I was talking about. This picture shows the inlet on the left side. I was planning to use one where the inlet is on the right side. It is not the fitting that has the low and high inlet. With this fitting (attached), can I vent the tub through this fitting as well? The top hub of this fitting will serve only venting purposes (for the toilet and the tub). Will this still work?

Why yes indeed you can use that fitting and a good choice it is also. Some call it an Estabrook, out here we call it a Cottage Tee. Very handy fitting and a real time saver too. Often overlooked.