Question 1b: The founder of Vanguard, John Bogle, said: "The idea that a bell rings to signal when investors should get into or out of the market is simply not credible. After nearly 50 years in this business, I do not know of anybody who has done it successfully and consistently."

This quote is most closely related to the theory of:

Select one:

a. Market efficiency.

b. Capital structure

c. Payout policy.

d. Working capital decision.

e. Term structure of interest rates.