The meaning of the word "quack" in this sentence from Poe's "The Cask of Amontillado" most likely means: "a person who dishonestly pretends to have skills or knowledge."
He seems to be using it as a synonym of <em>"charlatan,"</em> since he contrast Fortunato's true knowledge of wines with his pretended expertise on painting and gemmary.
Animal research played an essential role in the development of Herceptin and Tamoxifen, two medications that have already saved the lives of thousands of women who have been diagnosed with breast cancer.
The answer is b because the other examples entail a person contemplating their own thoughts or emotions, while option b shows someone in conflict with something other than themselves.
