What advantage does a metal backing give to a single-groove weld? It reduces the weld's cost. It makes the weld more ductile It reduces the hydrogen in the weld. It makes the weld stronger and of higher quality.

## Step 1<br />The problem is asking about the benefits of using a metal backing in a single-groove weld. The options provided are:<br />- It reduces the weld's cost.<br />- It makes the weld more ductile.<br />- It reduces the hydrogen in the weld.<br />- It makes the weld stronger and of higher quality.<br /><br />## Step 2<br />The use of a metal backing in a single-groove weld is a common practice in welding. This is because it provides additional support to the weld, which can help to reduce the risk of cracking and other defects.<br /><br />## Step 3<br />The metal backing also helps to distribute the heat of the weld more evenly, which can improve the overall quality of the weld. This is because the metal backing can help to prevent the weld from overheating in certain areas, which can lead to defects.<br /><br />## Step 4<br />The metal backing does not necessarily reduce the cost of the weld, make the weld more ductile, or reduce the hydrogen in the weld. These are not the primary benefits of using a metal backing in a single-groove weld.