I search an intuitive way to display a choice between two options with a specific ComboBox for each option.

I thought about the following mockup:

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![mockup](http://i.stack.imgur.com/lEzAE.png)

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Or maybe a navigation by "tab", with a ComboBox per tab:

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![mockup](http://i.stack.imgur.com/pu6Y4.png)

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But the content is really similar between both tab.

I can't directly ask the users now and the feature is a bit "urgent" but I'd like to offer something with a nice UX.

Do you have a suggestion for this kind of user choice/selection?