It means that you have no control over your mind. It does what it wants. Similar to how we are given a name that we had no say in choosing, this person is simply accepting that they will have certain thoughts because it’s not by choice.
Answer: Hm well personally I think none of the above. I think you should take a scientific question and research it (ie. What happens if you burn soap bars) but I guess if I had to choose one from here then A?