I would say option B. In option A if you are serving up dinner at the table you have to keep walking past the island - could drive you mad over time. Also option B gives you the capability of having a more formal space for dining should you want it on occasion. I would consider having a hob/sink in your island in option B then you can cook and talk to guests/family whilst you are doing it without having your back to them. We have this arrangement and its great - whether its the kids doing homework or guests having a glass of wine before dinner. In option B I would also swap your sofas around - with chaise longue along the bottom wall of the plan and two seater against the office wall - this will give you more space at the opening to actually get into this living area.