问题
单项选择题
The implication in this passage is that ______
A．only a German physicist could discover such a theory
B．quantum theory, which led to the development of twentieth century physics, is basically a mathematical formula
C．Planck's constant was not discernible before 1900
D．radiation was hard to study
答案
参考答案：B
解析：[分析] 推断题型。 见文章第二段的第一和第二句：Planck introduced an idea that led to the quantum theory，which became the foundation of twentieth century physics，In December 1900，Planck worked out an equation that described the distribution of radiation accurately over the range of low to high frequencies．可推出：导致20世纪物理学发展的量子论基本上是一个数学公式，所以选项B正确。