The answer is the first one.
In "Writers often disavow the notion of a 'literary duty'" the author conveys a somewhat condescending attitude, as if they would always follow this and set aside anyone who said otherwise. This attitude says the author is looking down on them, and that the author believes that many authors do not meet their standards.
Another answer I would consider is "...writers ruined by their shrill commitments." However, there is no context or clear tone. The author could be mournful of the lost potential for all we know.
No context? about this passage
It's told in first person (hope this helps you out)!
The Alchemist is the best inspiration novel I have ever read.
If you want to read just for entertainment then you may try the Harry Potter Series.
Answer, B) the strength of the speakers feelings