A satisfactory AP lumbar spine radiograph is made using 200 mA, 0.25 seconds, 78 kVp, and 40-inch SID. Which of the following technique changes will produce a radiograph of similar density while providing less contrast and less exposure to the patient? 200 mA, 0.12 seconds, 90 k Vp, 40-inch SID KVPT MASS b. 100 mA, 0.25 seconds, 78 kVp, 40-inch SID 200 * . 25 : c. 200 mA, 0.20 seconds, 78 kVp, 36-inch SID XI d. 400 mA, 0.12 seconds, 78 kVp, 40-inch SID