You should evaluate both of the options and do the following:
Ask your boss why she thinks Solution A is a better option as compared to Solution B (your solution). Try to have a productive discussion and dig deeper into her perspective. If you find out certain limitations in her solution, you should put it forward.
You should note that both you and your boss have the intention of doing good to the product. However, different people have different perspectives and communication plays a key role here. If you communicate with your boss clearly and prove that your solution is better, I think she will understand.
However, if the discussions aren't fruitful and you are indecisive - maybe the whole team can meet and take each other's opinion? In the end, your company has built a team to solve the technical problems. So, it may be a good idea to involve other developers from the team in the discussion and have a general chat.