15. Two important elements of the dividend policy irrelevance proposition are: A. all investors have homogeneous dividend needs and time horizons. B. dividends are paid even if a positive NPV opportunity exists and investors can re-arrange their own dividend streams. C. investors can re-arrange their own dividend streams and the investment policy is set and unaltered by the change in dividend policy. D. all investors have homogeneous dividend needs and dividends are paid even if a positive NPV opportunity exists. E. investors can re-arrange their own dividend streams and the source of financing must be debt