Which one is not necessarily true? a. An efficient portfolio has the highest possible expected return for a given standard deviation. b. An efficient portfolio has the lowest possible standard deviation for a given expected return. c. If a portfolio has the lowest possible standard deviation for a given expected return, it is an efficient portfolio. d. If a portfolio has the highest possible expected return for a given standard deviation, it is an efficient portfolio. e. All of the statements are true. An investment fund analyzes 150 stocks in order to construct a mean-variance efficient portfolio constrained by 150 investments. They will need to calculate different expected return terms and different variance covariance terms for returns. a. none of the other options b. 11250, 11325 C. 150, 11250 O d. 150, 150 e. 150, 11325 Suppose the stock now sells at $100, and its price will either increase by 20% or decrease by 20% by the end of the year. The risk-free rate from now to year-end is 5%. Which of the following options written on this stock that expires at year end must have the highest price? a. A call option with strike price of $120. b. A call option with strike price of $110. C. A put option with strike price of $90. d. A put option with strike price of $80. e. Not enough information