An electron beam targets and melts together layers of powder.

• A. Selective Laser Sintering (SLS)
• B. Stereolithography (SLA)
• C. Direct metal laser sintering (DMLS)
• D. Electron Beam Melting (EBM)

Answer: (D)

The description points to metal powder bed fusion using an electron beam. In this process, an electron beam—a stream of high-energy electrons—is directed at a bed of metal powder inside a vacuum chamber, melting the powder locally and fusing it to the layer below. The build is created layer by layer as the platform lowers and a new powder layer is spread. This is why the method is called Electron Beam Melting. Other options use different energy sources or materials: laser-based methods (like those used in Direct Metal Laser Sintering) melt metal with a laser, while Selective Laser Sintering and Stereolithography typically handle polymer powders or photopolymer resins, not metal powder with an electron beam.