Option 1 -> The passage indicates he avoided providing unnecessary hope or agreeable words, not emotional support.
Option 2 -> There is no mention of complex medical jargon in the passage.
Option 3 -> The passage explicitly states "Long years of practice had bred in the doctor a certain curt truthfulness; for that very reason, his opinion was valued."
Option 4 -> The passage does not mention anything about him never making mistakes.
Hence, Option 3: His blunt and truthful nature -> The passage directly connects his "curt truthfulness" to why his opinions were valued, describing him as "a judge pronouncing a verdict" rather than just a doctor giving opinions. His straightforward honesty, despite being harsh at times, earned him trust and respect -> correct