According to the principle of dominance, which of the following assets you would invest?

Asset $Y$ with $E[r]=10\%$ and StDev $=10\%$

Asset $x$ with $E[r]=10\%$ and StDev$=5\%$

Asset $W$ with $E[r]=5\%$ and StDeV$=5\%$

Asset $Z$ with $E[r]=5\%$ and StDev$=10\%$

What is the efficient frontier of risky investments?

The portfolio that offers the lowest risk$-$adjusted expected return.

Set of assets$/$portfolios that offer the lowest expected return for a given level of risk.

The portfolio that offers the highest risk$-$adjusted expected return.

Set of assets$/$portfolios that offer the highest expected return for a given level of risk.