Combining a risk-free asset with a portfolio of risky assets results in all of the following EXCEPT:（）

A. the standard deviation of the expected return for the newly created portfolio is the linear proportion of the standard deviation of the risky asset portfolio and the expected return for the newly created portfolio is the weighted average of the return on the risk-free asset and the expected return on the risky asset portfolio. 

B. the efficient frontier becomes the line that connects the point in the risk-return plane representing the risk-free asset, with the point representing the risky asset portfolio. 

C. all risk-return combinations between the risk-free asset and the risky asset portfolio can be represented by a straight line that connects the point in the risk-return plane representing the risk-free asset, with the point representing the risky asset portfolio.