What process involves pouring molten metal into a mold to produce a desired shape?

The process involving pouring molten metal into a mold to produce a desired shape is known as casting. In casting, molten metal is first heated until it becomes liquid and then is poured into a pre-shaped mold that defines the final geometry of the part. Once the metal cools and solidifies, it takes on the shape of the mold. This method is versatile and can be used to create complex shapes that may be difficult or impossible to achieve through other manufacturing techniques.

Casting is widely used across various industries due to its ability to produce intricate designs with high dimensional accuracy and surface finish. It also allows for the use of various metal alloys, making it suitable for a broad range of applications, from automotive components to artistic sculptures.

Welding involves joining two or more pieces of metal together using heat and/or pressure rather than forming a shape from a liquid state. Forging is a process of shaping metal by applying compressive forces, typically involving solid metal rather than molten metal. Extrusion consists of forcing material through a die to create long shapes with a constant cross-section and does not involve pouring molten metal into a mold. Thus, casting stands out as the appropriate answer for this question.