Final answer:
The core product for the Martha Stewart CBD line is 'A) Feeling good,' as this represents the essential benefit or value the consumer seeks from the product.
Step-by-step explanation:
The core product for items in the Martha Stewart CBD line is essentially what the consumer is fundamentally purchasing. In the context of the Martha Stewart CBD line, the core product would not be the wide range of flavors or the brand name itself, but rather the benefit or value that the product provides, which is to help people feel good. So the correct answer would be A) Feeling good.