compare two columns return info from a third but do not repeat

Hello, I have a difficult problem that I'm not sure has an answer. I have a table in the following format:

name type rating cost selected
A ab 10 20 0
B ab 5 25 1
C ac 7 7 0
D ac 6 5 1
E ac 8 17 1
F ac 15 13 0
G ad 14 9 0
H ad 7 4 1
I ad
...

What I'm trying to do is create a summary of selected types in a separate area on the same sheet or a separate sheet. What the formula needs to do is look at the selected column for a "1" (this could also be yes/no) and match that with the type designation "ab" or "ac" or "ad" and return the name into a separate cell in the summary area of the sheet. My problem is, I cannot have repeated items. For example, I can have only one type of "ab", two types of "ac", three types of "ad", one type of "ae", one type of "af", and one type of "ag". For example, if an item has been selected ("1"), and it is of type "ac", I need a formula that returns the name of that individual. Then, when a different one of the same type has been selected ("1"), I need the cell below to indicate the name of that type, without repeating the name of the type above. Can this be accomplished or is it too difficult? I've attached the spreadsheet so you can see what I mean, thanks.