48. What does Timothy Salthouse say about people's minds in most cases?
- A. They tend to decline in people's later years.
- B. Their flexibility determines one's abilities.
- C. They function quite well even in old age.
- D. Their functioning is still a puzzle to be solved.
答案：C
答案句：The results do not mean that young adults need to start worrying about their memories. Most people's minds function at a high level even in their later years, according to researcher Timothy Salthouse.
参考译文：研究结果并不意味着年轻人需要开始担心自己的记忆力。据研究员蒂莫西·索尔特豪斯称，大多数人的心智即使在晚年也处于高水平运作。
定位线索：题干“Timothy Salthouse say about people's minds in most cases”→答案句“Most people's minds function at a high level even in their later years”；文中“function at a high level”对应选项“They function quite well even in old age”。
解析：题干问索尔特豪斯关于大多数情况下人们心智的说法，答案句明确指出“大多数人的心智即使在晚年也处于高水平运作”，即“即使在老年也运作良好”，与C选项对应。A选项“在晚年倾向于衰退”与原文相反；B选项“它们的灵活性决定一个人的能力”、D选项“它们的功能仍是一个待解的谜”均未在原文提及，属于无中生有。
50. According to Salthouse, their study may help us.
- A. find ways to slow down our mental decline
- B. find ways to boost our memories
- C. understand the complex process of mental functioning
- D. understand the relation between physical and mental health
答案：A
答案句：“By following individuals over time,” Salthouse said, “we gain insight in cognition changes, and may possibly discover ways to slow the rate of decline.”
参考译文：索尔特豪斯说：“通过长期跟踪个体，我们能深入了解认知变化，并可能发现减缓衰退速度的方法。”
定位线索：题干“their study may help us”→答案句“we gain insight in cognition changes, and may possibly discover ways to slow the rate of decline”；文中“discover ways to slow the rate of decline”对应选项“find ways to slow down our mental decline”。
解析：题干问这项研究可能帮助我们做什么，答案句明确指出“可能发现减缓衰退速度的方法”，即“找到减缓智力衰退的方法”，与A选项对应。B选项“找到增强记忆的方法”、C选项“理解心理功能的复杂过程”、D选项“理解身体和心理健康的关系”均未在原文提及，属于无中生有。