The Term "Litmus Test" Is Commonly Used to Mean a Totally

Multiple Choice

The term "litmus test" is commonly used to mean a totally definitive test. In chemistry litmus is used as an acid-base indicator. Which of the following properly relates the chemical and common usages of the term "litmus test"?

A) Common usage is correct because the litmus test definitively defines a substance as an acid or a base.
B) Common usage is correct because litmus dye changes color at pH = 7.
C) Common usage is incorrect because litmus dye changes color over a range, most of which is above pH = 7.
D) Common usage is incorrect because litmus dye changes color over a range, most of which is below pH = 7.