Consider the below and then answer the related question.

You have computed the correlations for different sets of stock returns. They are as follows:$$ Stocks P and N Correlation $=0\mathrm{.}80$;$$ Stocks P and L Correlation $=0\mathrm{.}98$; Stocks P and Y Correlation $=0\mathrm{.}62$; Stocks P and T Correlation $=0\mathrm{.}77$

Each stock has the same expected return of $11\mathrm{.}05\%$ and their standard deviations are all equal at $22\mathrm{.}76\%.$

Your goal is to maximize your return per unit of risk. If your entire portfolio is now composed of Stock P and you can add some of$$only one$($N$,$ L$,$ Y or T$)$ stock to your portfolio,$$which stock would you choose?