You enter all of them if you have multiple entries. The "a, b, c, d, e" part are the line numbers for box 12. You may have more than one entry there and you can add additional rows in Turbo Tax (see attached screenshot). Use the add another row option to add as many rows as needed. As for your paycheck deduction, it depends on what type of contribution you are referring to - if its 401(k), then that would be whatever line number has "code D." I have included a link below with an explanation of the different codes.
Example: You may have multiple lines that look like the below. You would add three rows and include all of these items separately, including the dollar amounts showing
12a code D $xx.xx
12b code DD $xx.xx
12c code W $xx.xx
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