According to the PMBOK® Guide, the Perform Quantitative Risk Analysis process is the process of numerically analyzing the combined effect of identified individual project risks and other sources of uncertainty on overall project objectives.

Numerical Analysis: Unlike Qualitative analysis, which uses subjective scales (like High/Medium/Low), Quantitative analysis uses mathematical modeling and data to provide a statistical approach to uncertainty.

Impact on Objectives: It specifically quantifies the potential project outcomes and their probabilities. It is used to estimate the likelihood of achieving specific project targets, such as finishing on a certain date or within a certain budget.

Tools and Techniques: Common techniques used in this process include Monte Carlo simulations, Decision Tree analysis, and Sensitivity Analysis.

Why other options are incorrect:

Option A: Compiling a list of known risks is the output of the Identify Risks process. Preparing responses is part of the Plan Risk Responses process.

Option B: Assessing probability and impact for every risk in the register is a characteristic of Perform Qualitative Risk Analysis. Quantitative analysis is often only performed on high-priority risks that have already been vetted qualitatively.

Option C: While Quantitative analysis provides the data needed to justify Contingency Reserves, the actual evaluation and allocation of reserves is an output of the Determine Budget and Develop Schedule processes. Quantitative analysis is the input that informs those calculations.