What would you wear to a formal evening wedding?

I am a guest at my brothers formal wedding wedding (March 25) that is in the evening. I have a couple of choices:
1. Black velvet, beaded bodice, sleeveless dress. Ankle length.
2. Light blue satin, halter gown with some embroidery around the waist. Ankle length.
3. Cream colored, draped bodice swags at neckline, black and sparkling flowers with a matching black cardigan. Knee length.
4. Forest green velvet suit, sheath dress underneath, matching jacket. Calf length.
Also, please tell why.
The cream dress is a small floral print but the print is all one color-black. It has some beading/sparkles on 50% of the flowers. Very understated.

the blue or cream. i’m a fashion designer and i can tell you that velvet is for the holiday seasons. its becoming spring and the other 2 choices are more acceptable. i don’t know exactly what they look like, but pick the one that’s more up to date. i don’t understand the 3rd one. a cream dress with a cowl neckline and is knee length. but it also has black sparkly flowers all over it? i’m confused.

FASHION [Edition #3]: 12 Summer Floral Outfits