Catalytic hydrogenation of polycyclic hydrocarbons

Recently I came across a question-[![enter image description here](https://i.stack.imgur.com/lwQod.jpg)](https://i.stack.imgur.com/lwQod.jpg)


The compound on the left undergoes catalytic hydrogenation to yield A(not B, according to the answer). My knowledge is limited to the stereospecificity of catalytic hydrogenation, and I don't know if it's regioselective as well or not. Why do we get A as a product and not B? There are 3 moles of hydrogen provided, so how to decide which 3 multiple bonds would be reduced in such a situation? Can someone provide me with a detailed answer?


