According to diversification principle in investm

According to diversification principle in investment, suppose you invest Stock X and Stock Y with equal funds, which of the following is not true？______.

A．If X and Y are perfectly negatively correlated, the risk of the portfolio is neither reduced nor increased.

B．If X and Y are perfectly negatively correlated, the risk of the portfolio is perfectly offset.

C．If X and Y are perfectly positively correlated, the risk of the portfolio is neither reduced nor increased.

D．If X and Y are totally independent with each other, the risk of the portfolio is reduced.

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