Exclusively inhabiting tropical countries such as Liberia, wild chimpanzees lack adaptations to seasonal variations in ultraviolet B (UVB) irradiance from sunlight; since UVB exposure enables vertebrates to synthesize vitamin D, this raises questions about how chimpanzees in mid-latitude zoos are affected by the lower and more variable UVB irradiance in those locations. In a study of zoo chimpanzees in Norway and other mid-latitude countries, Sophie Moittié and colleagues found not only that chimpanzees' vitamin D levels correlate with UVB irradiance but also that vitamin D levels show no evidence of plateauing as UVB irradiance reaches its highest local levels, suggesting that __________
Which choice most logically completes the text?
A. averaged across seasons, vitamin D levels in zoo chimpanzees in mid-latitude countries such as Norway tend to be comparable to those in wild chimpanzees in tropical countries such as Liberia.
B. adaptations to seasonal variations in UVB irradiance may be emerging in zoo chimpanzees in Norway and other mid-latitude countries.
C. zoo chimpanzees in Norway and other mid-latitude countries tend to synthesize less vitamin D than they are inherently capable of synthesizing.
D. providing supplemental vitamin D to chimpanzees in zoos in Norway and other mid-latitude countries would likely not be beneficial.
文本翻译：
仅生活在像 Liberia 这样的热带国家中的野生黑猩猩，并没有适应来自阳光的紫外线B（UVB）辐射的季节性变化；由于UVB照射使脊椎动物能够合成维生素D，这就引发了一个问题：生活在中纬度动物园中的黑猩猩，如何受到这些地区较低且变化更大的UVB辐射的影响。在一项针对 Norway 及其他中纬度国家动物园黑猩猩的研究中，Sophie Moittié 及其同事发现：黑猩猩的维生素D水平不仅与UVB辐射强度相关，而且当UVB辐射达到当地最高水平时，维生素D水平也没有出现“平台期”（即没有停止上升的迹象），这表明：__________
文本分析：
文本结构非常清晰，是典型的 背景 → 问题 → 研究发现 → 推论：
① 背景与问题
野生黑猩猩生活在热带 → UVB稳定 → 不需要适应季节变化
→ 但中纬度地区UVB更低且波动大 → 可能影响维生素D合成
② 研究发现（核心证据）
两点关键信息：
维生素D水平与UVB 正相关
没有平台期（no plateau）
“没有平台期”的关键含义：
即使UVB已经达到当地最高水平，维生素D仍然在继续上升
→ 说明 还没有达到生理极限
③ 推论逻辑（填空）
如果“没有达到上限” → 说明：
当前环境下UVB 不足以让其达到最大合成能力
换句话说：
实际合成量 低于其本可以达到的水平
选项分析：
A. averaged across seasons, vitamin D levels in zoo chimpanzees in mid-latitude countries such as Norway tend to be comparable to those in wild chimpanzees in tropical countries such as Liberia.
错误。
文中没有进行“动物园 vs 野外”的比较，更没有说“相当”。属于无中生有比较。
B. adaptations to seasonal variations in UVB irradiance may be emerging in zoo chimpanzees in Norway and other mid-latitude countries.
错误。
文中没有任何“正在适应/进化”的信息。
“没有平台期”只说明没到上限，不代表产生了适应。属于过度推断。
C. zoo chimpanzees in Norway and other mid-latitude countries tend to synthesize less vitamin D than they are inherently capable of synthesizing.
正确。
逻辑完全对应：
没有平台期 → 没达到最大值
→ 当前合成量 < 潜在能力
D. providing supplemental vitamin D to chimpanzees in zoos in Norway and other mid-latitude countries would likely not be beneficial.
错误。
逻辑相反：
既然没达到上限 → 补充反而可能有帮助
属于反向推断错误。
扫码获取SAT推理题合集
