Which phrase does the author use to convey the ideas that the scientists' work was "treacherous"?

Pls due today which excerpt from the text most effectively demonstrates that the narrator's point of view about the cabuliwallah has changed? "i felt a little sorry, and would have called him back, but i found he was returning of his own accord." "i sent for mini immediately from the inner apartment. many difficulties were raised, but i would not listen." "tears came to my eyes. i forgot that he was a poor cabuli fruit-seller, while i was—. but no, what was i more than he? he also was a father." "i took them and was going to pay him, but he caught my hand and said: "you are very kind, sir! keep me in your recollection. do not offer me money! —"