Which tool features a U-shaped opening with a fixed jaw for gripping nuts and bolts?

• A. Open End Wrench
• B. Framing Square
• C. Reciprocating Saw
• D. Reflective Orange Triangle With Red Border

Answer: (A)

When turning nuts and bolts, the key is how the tool grips the fastener. A U-shaped opening with fixed jaws fits around the flats of a hex nut or bolt and allows you to apply torque by pulling or pushing on the handle. This design is the defining feature of an open-end wrench: it grips two opposite sides of the fastener with its fixed jaws and lets you work in confined spaces where a socket or other tool won’t fit.

The other items don’t serve this purpose. A framing square is a layout and measurement tool used for checking right angles. A reciprocating saw is a cutting tool. A reflective orange triangle with a red border is a safety signaling device.