Their are lots of methods on being astute (:
Your should put your cited source on a separate sheet of paper at the end of your article
Answer:
It produces shivers down the spine, or a feeling of unease.
Explanation:
The narrator hasn't said anything in this excerpt that makes them hard to believe, or unreliable. This excerpt is not particularly optimistic either. There is no blood and gore, but the narrator is clearly made uncomfortable by the painting. So the excerpt produces shivers down the spine, or a feeling of unease.