47.) The parking brake will not hold on a vencle equipped with four-wheel disc brakes and integral parking brake rear calipers. Which of these could be the cause? OA. A failed master cylinder OB. A restricted brake hose OC. A failed brake booster OD. Seized rear calipers

## Step 1<br />The problem is about diagnosing a fault in a vehicle's braking system, specifically the parking brake. The parking brake is a system that allows the vehicle to be stationary when parked. It is usually connected to the rear brakes.<br /><br />## Step 2<br />The problem states that the parking brake is not holding on a vehicle equipped with four-wheel disc brakes and integral parking brake rear calipers. This indicates that the issue is related to the rear brakes.<br /><br />## Step 3<br />Looking at the options, we need to identify which one could cause the parking brake to fail. <br /><br />## Step 4<br />Option A, a failed master cylinder, would affect all brakes, not just the parking brake. <br /><br />## Step 5<br />Option B, a restricted brake hose, would also affect all brakes, not just the parking brake. <br /><br />## Step 6<br />Option C, a failed brake booster, would affect all brakes, not just the parking brake. <br /><br />## Step 7<br />Option D, seized rear calipers, would directly affect the parking brake since it is connected to the rear brakes. If the rear calipers seize, the parking brake would not be able to hold the vehicle stationary.