Final answer:
Rotating a square about a line lying on one of its sides produces a cylinder, where the diameter of the cylinder corresponds to the side length of the square. The correct answer to what solid 3D object is produced by rotating the square about line m is (B) A cylinder with diameter.
Step-by-step explanation:
When a square is rotated about a line that lies on one of its sides (line m), the 3D solid object that is produced is a cylinder. Specifically, if we consider the rotation axis to be along one side of the square, the distance from this axis to the opposite side of the square (which is the length of a side of the original square) becomes the diameter of the cylinder after rotation. Thus, the correct answer to what solid 3D object is produced by rotating the square about line m is (B) A cylinder with diameter.