【正确答案】 A

【答案解析】解析：由第一段和第二段前两句可知，文章主要在讲人们对于疼痛态度的转变。过去对于疼痛习以为常，现在人们对疼痛更加重视。故选A。

【正确答案】 D

【答案解析】解析：由文中“pain is now considered the fifth vital sign，as important as blood pressure，temperature，breathing rate and pulse in determining a person’s well—being”可知疼痛现今被认为是第五大生命迹象，其他还有血压、体温、呼吸频率还有脉搏。故选D。

【正确答案】 C

【答案解析】解析：由文中“That’s why a growing number of hospitals now depend upon physicians who specialize in pain medicine…we also help provide comprehensive therapy for depression and other psychological and social issues related to chronic pain”可知现在越来越多的医院都依靠疼痛专科医生是因为疼痛专科医生还可以对抑郁症或是其他与慢性疼痛相关的心理领域提供综合治疗的帮助，故选C。

【正确答案】 B

【答案解析】解析：由文中“Decades ago，there were only a limited number of drugs available，and many of them caused significant side effects in older people，including dizziness and fatigue”可知几十年前止疼药的种类有限，并且会有晕眩和疲劳的副作用，故选B。

【正确答案】 D

【答案解析】解析：由文中“Such comprehensive therapy often involves the work of social workers，psychiatrists and psychologists，as well as specialists in pain medicine”可知综合性治疗需要社工、心理学家和疼痛专家的共同合作才能完成，故选D。