Which swimsuit should I buy?

Today I went through my swimwear and threw away the stuff that was old, so I figured I might as well update my inventory.

I already own enough two-piece bikini sets of various types, I feel that I should have a one-piece or two. Which one should I buy? I have 4 picked out on the Brigittewear website, but I couldn't make my mind up, so I'm leaving it up to you all.
This is the first one I saw that really caught my eye. See-through sheer back, but it all looks flattering.
A Baywatch-style onesie. I've always had a thing for high-cuts.
Yes, this one's topless. If I were to wear it in public I'll have to wear it with a shirt or a top. I'm often topless while swimming at home anyways.
This one shows some really nice sideboob.
Select gender and age to cast your vote:
Updates
+1 y
Update: I've decided to order both B and D. Thanks for the opinions.
Which swimsuit should I buy?
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