Which analytical method measures the amount of light scattered by the particles in solution?

Nephelometry is the analytical method that measures the amount of light scattered by particles in a solution. This technique is particularly useful for analyzing suspensions and solutions containing particulate matter, such as proteins or microorganisms. In nephelometry, a light source (often a laser or an LED) is directed at the sample, and the scattered light is detected at a defined angle from the original beam. The amount of light scattered is proportional to the concentration of particles in the solution, allowing for quantitative analysis.

The other methods listed serve different purposes. Fluorometry measures the fluorescence emitted by a sample upon excitation with light, which is useful for specific compounds that fluoresce but does not involve scattering of light in the same way. Spectrophotometry, on the other hand, measures the absorption of light by a sample, not scattering, which is more suitable for solutions where the analyte absorbs light at specific wavelengths. Chromatography is a separation technique rather than an analytical measurement method; it separates components in a mixture based on different properties and does not directly measure light scattering or absorption.

Thus, the unique feature of nephelometry in analyzing light scattering makes it the correct choice for this question.