What Is the Similarity Between a Stock Market and a Labor

What is the similarity between a stock market and a labor market?

A) Both use a barter system to facilitate the exchange of products.
B) Both are composed of people who are unwilling to spend large sums of money for products or services.
C) Both are composed of people with specific wants that can be satisfied by particular product categories.
D) Both deal in selling high-end,consumer durable products.