Which of the Following Statements Represents Related-Constrained Diversification

Which of the following statements represents related-constrained diversification?

A) A firm earning more than 95 percent of the revenues from a single line of business
B) A firm that earns more than 70 percent of its revenue from its main line of business and the rest from businesses located along the value chain
C) A firm that earns less than 70 percent of its revenue from its main line of business and whose other lines of business share product, technological, and distribution linkages with the main business
D) A firm that earns more than 70 percent of its revenue from its main line of business and the remainder from other lines across different value chains