A risk-averse investor can borrow and lend at the risk-free rate of 5%. Which of the following risky portfolios should s/ he hold in combination with a position in the risk-free asset? portiolio with a standard deviation of 14% and an expected return of 16% (option B) portlolio with a standard deviation of 12% and an expected return of 16% (option A) any of AB or C portfolio with a standard deviation of 16% and an expected return of 14% (option C) none among A,B and C