Answer:
D. Decide whether they have designed the best possible product.
Explanation:
Since the engineers are just starting out on a new product, their priority might not be centered on wether they have designed the best product possible. After the initial design, this question can pop up and beta versions can be tested and incorporated for a future use. This question would mostly be solved by the research and development arm of the start up after a launch. It would mostly rely on the success of the original design.