In Terms of Strategy Making,what Is the Difference Between a One-Business

In terms of strategy making,what is the difference between a one-business company and a diversified company?

A) The first uses a business-level strategy,while the second uses a set of business strategies and a corporate strategy.
B) The first uses a business-level strategy,while the second uses a corporate-wide strategy.
C) The first uses an operating strategy,while the second uses a business-line strategy.
D) The first uses a functional strategy,while the second uses a business-line strategy.
E) All of these.