Answer:
true
Explanation:
Assume, original stock was A. Now a new stock B is added.
Weight of Stock A in the portfolio=Wa
Weight of Stock B in the portfolio=Wb
Standard Deviation of Stock A=Sa
Standard Deviation of Stock B=Sb
Cova,b=Covariance between Aand B
Portfolio Variance=(Wa^2)*(Sa^2)+(Wb^2*Sb^2)+2*(Wa*Wb*Cova,b)
Correlation between A &B=(Cova,b/Sa*Sb)
Cova,b=Sa*Sb*(Correlation between A&B)
Hence,higher the correlation between A&B, higher will be the covariance (Cova,b).
Hence higher will be the Portfolio variance.
So, the reduction of risk will be lower.