The efficient set of portfolios:
contains the portfolio combinations with the highest return for a given level of risk.
contains the portfolio combinations with the lowest risk for a given level of return.
is the lowest overall risk portfolio.
Both contains the portfolio combinations with the highest return for a given level of risk; and contains the portfolio combinations with the lowest risk for a given level of return.
Both contains the portfolio combinations with the highest return for a given level of risk; and is the lowest overall risk portfolio.