Four regional less-than-truckload (LTL) carriers handle shipments traveling from Lexington, Kentucky, to Springfield, Illinois. All four companies say that their normal service time to deliver these shipments is two business days. The four carriers compete with each other on the basis of price and service quality rating, as shown in the following table. The price reported in the table is the (nondiscounted) cost per hundredweight (cwt) of sending a 600-pound shipment from Lexington to Springfield at freight class 70. The service quality rating measures a carrier's loss and damage record and goes from 0 (poor quality) to 100 (high quality). Which of these LTL carriers are on the efficient frontier? Carrier A B B Price $103.90 $98.50 $127.20 $111.40 Service Quality Rating 95 91 98 94 D