Cost classification can be done in .a.two ways.b.three ways.c.several ways.d.four ways.

Cost classification is a crucial aspect of cost accounting that allows businesses to categorize costs based on different criteria for better financial analysis and decision-making. The classification can indeed be done in several ways.

1. By Nature: Costs can be classified based on their intrinsic nature, including materials, labor, and overhead costs.

2. By Behavior: This classification divides costs into fixed, variable, and semi-variable (or mixed) costs, depending on how they respond to changes in production levels.

3. By Function: Costs are also classified based on their functions in the organization, such as production costs, administrative costs, selling and distribution costs, etc.

Each of these classifications serves different purposes and offers unique insights into the financial status and operations of a business. While some resources might indicate two, three, or four ways of classifying costs, it is generally accepted that classification can occur in several different ways based on the analytical needs of the business. Therefore, the best option would be c. several ways.