Answer:
Option D is not correct
Step-by-step explanation:
Diversification is a method which is used to reduce firm-specific risk. Investors try to construct a portfolio which helps to maintain a reasonable profit. Market risk which is the Beta cannot be eliminated and every firm has to bear it, no matter how the portfolio is constructed. For example, if an investor invests in two stocks, if one stock goes down the other will compensate the negative returns. So, diversification is a technique to reduced firm-specific returns.