For a Market to Exhibit Semi-Strong Form of Efficiency, Which

For a market to exhibit semi-strong form of efficiency, which of the following situations must exist?

A) New information is available to all investors who immediately act upon it establishing the best estimate of the worth of the stocks.
B) The cost of capital is the same for each investor in the market.
C) A large numbers of investors are immediately motivated by new information to trade shares establishing the best estimate of the worth of the stocks.
D) A single investor is motivated by new information to trade shares resulting in the best estimate of the worth of the stocks.
E) The risk premium demanded is the same for each investor in the market.