Which tool is best for tightening nuts and bolts?

A wrench is specifically designed for tightening and loosening nuts and bolts, making it the best tool for this purpose. It typically features a long handle that provides leverage, allowing the user to apply significant torque without excessive effort. Wrenches come in various styles, such as open-end, box-end, and adjustable, each suited for different types of fasteners and situations.

The hammer is more suited for driving nails or fitting parts together rather than tightening screws or securing nuts. Similarly, a screwdriver is designed for turning screws, not nuts and bolts. Pliers, while useful for gripping and turning, do not provide the same level of torque and precision needed for effectively tightening nuts and bolts as a wrench does. Therefore, the wrench is the appropriate choice for this task.