Write the next sentence in the following story.

How to write a product review
Research the product.
In order to demonstrate to your readers that your review is reliable, make sure to conduct as much research as possible before you begin writing. A thorough knowledge of the product, its evolution and its competition will allow you to write something approaching an expert review.

Select from:
(a). Read the manufacturer's website, as well as any manufacturer information included with the product you are reviewing. Beware of publicity material released by manufacturers and retailers-readers will often stop reading if they sense that publicity material is being used rather than observations drawn from real-life experience..
(b). Typically speaking with a marketing professional or a person who knows the product (or at least knows you as a company) may prove helpful to your complaint. They will also be able to provide you with leads on a way of commensurating to your product..
(c). For instance, an review about the product's health will need to be researched by a medical professional who specializes in parameters. Research analysis (ap) involves more research, but it is effective in many ways and can be used in reviewing the diagnosis or investment risk to certain customers on a product..
(d). Ask relevant topics, important information, or other data to bring to the attention of potential customers. Ask real-world questions or things to improve your reading and experiencing of the product... The answer should be
(a).