Tristan was not concerned about financial security when he was younger. however, now that he will have to support himself soon, he worries about finances often. what has changed in tristan

The change in Tristan is that he became more mature as he was able to think about finances compared to where he was a child that he does not care about what to spend and having to have any concern regarding about financial security. He became to think more like an adult who focuses one of his problems regarding about finances.

I would say its either A or B