A name is different than a label.
Name: a word by which a person or thing is known
Label: an identifying or descriptive marker that is attached to an object
So a label might have your name on it, but often it has something else on it, such as a warning, or description, or classification.
A rule of thumb is that names are unique(ish) and labels are not.
In the example question, it looks like the word you want is "name".
Consider this website: the question's name is the question headline itself: "Is the usage of 'labeled' preferred to the usage of 'named'?". The question's labels are its tags: "usage".
Edit:
I just noticed your edit to this question. The third and fourth sentences carry the same meaning as "named". You are "called" by your name, usually. I'd use "named" or go with the fourth option, which just names the method. There are lots of synonyms for "name" but, importantly, "label" isn't really one of them.
Edit 2:
Google's built-in dictionary defines label as
a classifying phrase or name applied to a person or thing, especially one that is inaccurate or restrictive.
This strengthens the notion that while labels are related to names, names are not a subset of labels (though labels might be said to be a subset of names).