One nanometer is equal to A. 10-6m B. 10-8m C. 10-9m D. 10-5m

The correct answer is C. 10-9m.

A nanometer is a unit of length in the metric system equal to one billionth of a meter (10-9 m). It is often used to measure the size of atoms and molecules.

Option A is incorrect because 10-6 m is equal to one micrometer.

Option B is incorrect because 10-8 m is equal to one nanoangstrom.

Option D is incorrect because 10-5 m is equal to one micrometer.