Emerald Ltd has accumulated the following data for the most recent 6- month period. Month July August September October Direct labour hours Maintenance services 27,000 $46,000 20,000 29,000 21,000 40,000 8,000 17,000 12,000 20,000 9,000 20,000 November December Management believes that maintenance cost is a mixed cost that depends on direct labour hours. Using the high-low method to estimate the variable component of this cost, the estimate would be closest to: Select one: O A. $0.69 per direct labour hour O B. $1.56 per direct labour hour O C. $0.66 per direct labour hour OD. $1.53 per direct labour hour