Which dress seems more suitable for professional wear?

I don't have a lifestyle that require business wear and where I live it's less common, but I always liked LBD (little black dresses) when you want something more "safe" but still being ME, like interviews and funerals.  But I often find it hard to find one that is not too short or too low neckline, but I'm a bit on the bustier side and longer legs so even the so called "work dresses" end ups a bit shorter.

My style is more towards an edgier dark style with a classic twist so I love wearing black. So personally I prefer the peplum one which is technically a top and a pencil skirt, but it's less "traditional". I'm pretty sure 4th is the most conservative one, but I'm not sure when it comes to midi dresses. It's worn with a blouse underneath because it's one of my summer dresses. 2nd and 3rd are more classic but they have the issue with neckline because I'm a 32 triple D (not a bust troll lol. just my fit problem area!).