I have a 1099-R. In box 7, code is listed as “4D.” I must select 1 or 2 codes that match this box. Do I enter code “4-Death”, or “4-Death” AND code “D-Annuity payments”?

It is two codes.  Enter the 4 and then enter the D in the box directly below where you entered the 4.

It's two separate codes and you have two separate boxes to enter them in.  Code 4 in the first box and code D in the second.