For a one-price monopolist, the marginal revenue curve is always: A equal to the demand curve.
B negative
C equal to the average-revenue crisis
D positive
E less than the average-revenue curve

Critics claim that the biological theory of personality may be problematic for research due to which of the following? a. there is already too much theoretical work concerning biological influences on personality. b. biological influences on personality are impossible to scientifically research. c. the biological theory provides little structure to direct or guide research. d. biological theorists have had difficulty establishing supportive research for the biological perspective.