Which can be true for diversified portfolios with more than one asset?
A. The correlation coefficient between the returns on two assets will always have a value between 0 and +1.
B. If the correlation is negative: returns tend to have opposite signs.
C. If the correlation is positive: the return on one asset is positive and the return on the other asset tends to be negative.
D. For a correlation of +1, the returns on the assets are not correlated.