Which slide option is most viable?

The part I drew up here is an example cross section of something I am designing to get die cast out of aluminum.

Style A has a draft on both sides, and the minimum slide size to form the lower pocket. The slide is centered on the parting line.

Style B has a flat bottom and is constructed like a 3 sided die.

Style C is the same part design as style B but uses the minimum slide size to achieve the flat bottom.

I'm not designing the die, just the part. I just want to make sure that it's okay to have a flat bottom on this part, or if it isn't and I need to keep the pocket slide as small as possible, and in that case, if there is any issue with having a slide on the parting line.