A. Why do you think honesty is important?

(Because once faith is lost, it's hard to believe.) --> Because once faith is lost, it's hard to believe again. => Corrected vocabulary.

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There's nothing special.  

I'm going to the aquarium. Do you want to come with me?  --> I'm going to the aquarium. Will you join me?  

Of course, I really want to go. --> Sure, I really want to go there.  

=> Your sentence has a correct grammatical structure, but this has the correct usage/ expression.

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