Which of the following is a hand-held powered tool that may be equipped with only a positive "on-off" control switch?

The correct answer is shears, which are a type of hand-held powered tool designed for cutting materials. These tools are often equipped with a simple, positive "on-off" control switch that allows the user to operate the tool safely and effectively. The design of shears typically prioritizes ease of use and safety, with the control switch only allowing for the tool to be powered on when actively engaged.

In contrast, reciprocating saws, drills, and tappers often feature more complex controls or variable speed settings, which are not limited to a mere on-off function. For safety and operational consistency, shears are designed to ensure that they will run only when the switch is actively engaged, minimizing the risk of accidental activation when not in use. This feature makes them particularly suitable for tasks requiring precision and control.