The correct answer is B.

Slope analysis in pricing is used to evaluate how pricing changes across product sizes or volumes. In retail pricing, larger sizes are often expected to provide a better price per unit of measure. CMKG explains that price guidelines can relate to product size and that price slope analysis can be used to ensure larger sizes provide a better slope. CMKG also lists slope as a pricing measure connected to discounting by volume of purchase and elasticity.

Option A is wrong because total revenue is a sales measure, not slope analysis. Option C is wrong because production cost comparison belongs to costing or activity-based costing, not price slope. Option D is wrong because profit margin analysis focuses on gross profit or margin percentage, not the unit-price relationship across pack sizes. The key test phrase is unit price decreases as purchase quantity increases. That is exactly what price slope analysis checks.