Which of the following statement(s) is (are) false about portfolio risk?

	a.	Negatively correlated stocks have rates of return that move in opposite directions
	b.	Combining stocks that are perfectly positively correlated will reduce the portfolio risk through diversification
	c.	The lower the correlation among the stocks in the portfolio, the lower is the portfolio risk
	d.	Positively correlated stocks have rates of return that move in the same direction