> Person B has two morally acceptable answers to this question, they can either say "Yes, I believe abortion is morally wrong" or "No, I don't believe abortion is morally wrong."

Why would you assume that these are the only two morally acceptable answers?

An equally morally acceptable answer would be *`It depends`* which is neither yes nor no.   

> This answer indicates that they have no interest in ethical discussions in society

No it does not. `I don't care ` could also mean that the person is lacking the capacity¹ to form (or have) an opinion on this matter. *It's definitely* not a *conclusive statement* **at all**.

¹ by "capacity" I mean _any_ capacity, like time or means to get to information etc. *not just* mental capacity.