The quantitative analysis answers which of the following questions?

The quantitative analysis is primarily concerned with determining the amount or concentration of a specific substance in a sample. This aspect of analytical chemistry involves measuring specific quantities to provide precise data regarding how much of a compound exists within a sample. Through various techniques such as titration, spectrophotometry, or chromatography, scientists can accurately quantify the concentration of analytes.

In the context of the question, selecting "How much?" directly aligns with the core purpose of quantitative analysis, which focuses on measuring and expressing the amount of a substance present. Understanding the quantity is essential for applications such as formulation, quality control, and environmental monitoring, where knowing the exact concentration is crucial for compliance, safety, and efficacy.

The other options discuss aspects like identification, purity, or location, which pertain more to qualitative analysis or other analytical techniques, rather than the specific goal of quantifying the amount of a substance.