Which of the Following Statements Is False

Which of the following statements is false?

A) Stock returns will tend to move together if they are affected similarly by economic events.
B) Stocks in the same industry tend to have more highly correlated returns than stocks in different industries.
C) Almost all of the correlations between stocks are negative, illustrating the general tendency of stocks to move together.
D) With a positive amount invested in each stock, the more the stocks move together and the higher their covariance or correlation, the more variable the portfolio will be.