The sales in thousands of a new type of product are given by S(t) = 210 -20 e ., where t represents time in years. Find the rate of change of sales at the time when t= 5. Round to the nearest tenth. O A. 1,598.2 thousand per year O B. - 0.2 thousand per year O C. 0.2 thousand per year O D. - 1,598.2 thousand per year