A man who is 5 foot 8 inches tall is losing weight at the rate of 4 pounds per month. Suppose that for a person of this height, the relationship between body mass index B and weight w (in pounds) is given by 4600B = 715w. Find the rate of change of body mass index with respect to time. Differentiate both sides of the equation with respect to time. dB dw 4600 = 715 dt dt Find the rate of change of body mass index with respect to time. Select the correct choice below and fill in the answer box to complete your choice. (Round to the nearest tenth as needed.) O A. The man's body mass index is increasing by BMI index points per month. O B. The man's body mass index is decreasing by BMI index points per month