According to this excerpt, the two brothers represent C. good and evil.
As you can see in this passage, the right-handed twin represents good - he lives in heaven, and watches over men, providing them with the help they need. On the other hand, we have the left-handed twin, who represents evil - he lives among men, and rejoices when he sees warfare and suffering.
It means that he has abided by certain mores for his whole life and by using the literal example of “pulling a thorn”, he’s saying, “there’s not one person who i haven’t helped, that’s what makes us brothers. When they need me i help them, and when i need them they help me.” It is interesting because he’s explaining that just because it’s not normal for you doesn’t mean it’s not my version of normal.
<h3>This is a late answer but It is C.. (I think *v*) Hope it helps <3 </h3>
I think blank slate is the best translation for tabula rasa.