To create "The Basics" as a combination of different products in Salesforce B2C Commerce, the appropriate step is to use the Product Bundles feature. A. In the Product Bundles module, create a bundle named “The Basics”. This option allows the developer to group multiple individual products into a single purchasable item, with its unique ID and inventory tracking as a bundle. Creating a product bundle is suitable for selling combinations of products as a package, which fits the scenario of selling "The Basics" as a combined product.

The Product Sets module (Option D) is typically used for grouping products for display purposes rather than selling them as a single SKU, which distinguishes it from the bundles. Detailed instructions and guidelines on creating product bundles are available in the Business Manager documentation under the "Product Bundles" section.