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

The target is to display a roadmap by a specific axis of analysis ('Department' or 'Business Domain') defined by the user. That's why I thought about the radiobuttons. 
And then, the user has to select a specific value in a combobox (or something else) for this specific axe.

I thought about the following mockup:

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![mockup](http://i.stack.imgur.com/k097O.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/VPdKh.png)

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But the content is really similar for each 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?