TBR Organic Chemistry Structure Elucidation #22

[CookieZine]

Which three-dimensional conformation corresponds to the 3-hydroxy-cis-decalin, shown below?

The hydroxyl group should be up, which allows us to eliminate C and D.

TBR says that the C-C bonds of the left ring must be one axial and one equatorial as a consequence of the hydrogens on the right ring being axial and equatorial. I don't follow their logic. Would the equatorial hydrogen on the first ring cause this orientation?

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[kfcman289]

The answer is B. The key is that they are all cis. That means the oh, h , and h will all be in the up most position or lowest position for that respective carbon. The oh, h, and h in B are all in the top most position for the carbons.