Answer: Breyer's new product was in the Market testing stage of the new-product development process.
Step-by-step explanation:
Market testing is a method where the product can be tested with sample production and sales to know the customer reaction towards the product. If the products are welcomed by the customers then companies will produce them in actual quantities.
In this case Breyer's has introduced new ice cream flavor which might be accepted by the people or not. So market testing of the new product is done as per the development process. Market testing also saves the company from product failure.