What tool is commonly used for laying out arcs and circles?

The tool commonly used for laying out arcs and circles is a compass. A compass consists of two arms, one with a pointed end and the other with a pencil or marking tool, allowing it to draw circles or arcs of a specific radius by fixing the pointed arm at the center point and rotating the pencil arm around it. This makes it particularly effective for tasks that require precision in curved designs or measurements.

In contrast, a protractor is mainly utilized for measuring angles, while a square is used for ensuring right angles and straight lines in construction. Tremble points seems like a misnomer; the correct term is likely 'plumb bobs' or similar devices used for vertical alignment rather than layout for arcs and circles. Therefore, the compass is the appropriate and most effective tool for this specific task.