Final answer:
Only a few (b) product ideas actually reach the production state due to a range of challenges in the development process.
Step-by-step explanation:
In the context of product development, it is known that (b) only a few of the ideas for new products, refinements, and extensions ever make it to the production stage. This is largely due to the various challenges involved in the process, such as technical feasibility, market demand, financial considerations, and logistical issues. A great deal of initial concepts are filtered out through a rigorous evaluation and development process before a select few can reach the production phase and enter the market.