Recommendation Portrait Lens for 5D2

On a Canon 5D2,

• what would you preferably use as portrait lens between those below,

• for snaps of kids mainly, without flash, indoor or outdoor (torso + head),

• wide open or stepped down max 1 stop:

1/ Canon EF 85mm f1.8
2/ Canon EF 100mm L IS f2.8
3/ Canon EF 24-105 L IS f4
4/ Sigma 150mm f2.8 (non OS version)

Criterias are: sharpness, contrast, color and bokeh

Thanks for your advise
--
Philippe

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