This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Pharmacology
[{'content': 'Astringents are substances that: \nSelect and explain. \nA. Irritate sensory nerve endings, B. Precipitate proteins, C. Penetrate target cell nucleus for their action, D. reduce inflammation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Astringents: They are substances that precipitate proteins. Eg: Tannic acid and tannins Tannic acid is present in many plants but is generally obtained from nutgalls of oak. Tannins are found in tea, catechu, nutmeg, areca nut (betel nut), etc. They denature proteins forming protein tannate. Alcohol or Ethanol and methanol are good astringents at 50-90% concentration. othe eg: are alum, acacia, sage, yarrow, witch hazel, bayberry, distilled vinegar, very cold water, and rubbing alcohol. Mild astringents relieve such minor skin irritations as those resulting from superficial cuts; allergies; insect bites; anal hemorrhoids ESSENTIALS of medical PHARMACOLOGY SIXTH EDITION -KD TRIPATHI Page:887', 'role': 'assistant'}]