Best liquid cooling radiator orientation?

alright all so i have a quick few of questions about how i should orient my 120mm single fan size liquid cooling radiator. i'm planning on installing it on the rear 120mm exhaust fan fixture in my antec 900 case. however i would like to know if i should:

a) have the fan taking in cool air from outside the case and blow it into the radiator which is inside the case.

b) have the fan blowing hot air out of the case and into the radiator which is inside the case.

c)have the fan mounted inside blowing hot air out with the radiator mounted outside the case

also, with this radiator one side of it has both nozzles for the cooling liquid to enter and exit. seeing as how both of these nozzles are on one side where should these be oriented; that is to say what edge of the square should they by on. top? bottom? one of the sides? or does it even matter?

heres my current radiator:

http://www.infotechnow.com/product [...] ts_id=6014

im liking that orientation better but i should also mention that on my case i have a 200mm exhaust fan at the top and that may counter balance the hot air coming in but i guess i'll just have to play around with it