Which of the following is an essential tool for a plumbing contractor?

A plumbing contractor relies on a variety of tools to effectively perform their duties, encompassing various tasks such as installation, repair, and maintenance of plumbing systems. Among these tools, a wrench is crucial for tightening and loosening nuts and bolts, especially in pipe fittings and valves. A hammer is instrumental in tasks requiring driving nails, helping in securing various fixtures or connections. Likewise, a screwdriver is essential for fastening screws, which is common in plumbing installations involving fixtures or components attached with screws.

Given that all three tools—the wrench, hammer, and screwdriver—are fundamental in carrying out the diverse tasks found within the plumbing trade, recognizing that they each serve a distinct purpose enhances the contractor's ability to address different challenges on the job. Therefore, the correct answer encompasses the idea that all of these tools are indispensable for a plumbing contractor's toolkit.