Which of the following statements is TRUE? A. Convexity is desired when interest rate volatility is expected to increase O B. Convexity introduces error to the duration model. O C. Convexity is valuable to investors because when interest rates drop, the price of a more convex bond increases more. O D. All of the above Question 4 3 pts Macaulay duration works well as a meaure of interest rate risk if: O A. The bond is fixed-rate, with embedded option. O B. The bond is fixed-rate, option-free. O C. The change in rate happens gradually. O D. Both A and B are correct