Which specific type of website allows users to voice their opinions on all kinds of products and services across every segment of the Internet market?

a Review sites

b. Social bookmarking sites

c Location-based social networking sites

d. Search sites

Answer: The correct answer is "a. Review sites."

Explanation: Review sites are those websites where users can provide their opinion through a brief review or a score on a particular product or service. This tool provides information to potential new customers about the quality of the product or service they are looking for, it also serves the producers of goods or services to know how they can improve.