Which of the following statement is correct?

A$.$ If the returns on two stocks are perfectly positively correlated $($i$.$e$.,$ the correlation coefficient is $+1\mathrm{.}0)$ and these stocks have identical standard deviations, an equally weighted portfolio of the two stocks will have a standard deviation that is less than that of the individual stocks.

B$.$ Diversifiable risk can be reduced by forming a large portfolio, but normally even highly$-$diversified portfolios are subject to market $($or systematic$)$ risk.

C$.$ If an investor buys enough stocks, he or she can, through diversification, eliminate all of the diversifiable risk inherent in owning stocks. Therefore, if a portfolio contained all publicly traded stocks, it would be essentially riskless.

D$.$ Portfolio diversification reduces the variability of returns $($as measured by the standard deviation$)$ of each individual stock held in a portfolio.

E$.$ If you add enough randomly selected stocks to a portfolio, you can completely eliminate all of the market risk from the portfolio.