It’s impossible for me to select one of them. They are all worth reading and worth remembering.
By curiosity, I took this Myers-Briggs test again today, which will give a good idea of what kind of introvert or extrovert you are. The result is still introvert for me (INTJ) even if I would say that I changed a bit since the last time I took it.
I don’t value this conclusion too much, but reading about introverts is helpful. Things that I find abnormal about me, especially when it comes to relationships with people, look a bit less unordinary.