Which printmaking technique involves making incisions into a metal plate?

The technique that involves making incisions into a metal plate is engraving. This printmaking method requires the artist to use a sharp tool called a burin to carve designs or images directly into the surface of a metal plate, typically copper or zinc. The incised lines hold ink during the printing process, allowing for fine details and precise imagery. This technique has historical roots in both art and commerce, used for making detailed illustrations and prints.

Engraving is distinct from other printmaking techniques like linocut and woodcut, which involve carving into softer materials such as linoleum or wood and rely on relief printing methods. In drypoint, while also a form of intaglio printmaking, the technique involves scratching directly into a plate's surface rather than incising it, which creates softer lines. Thus, engraving uniquely characterizes itself by the methodical incision into metal, making it the correct answer to the question.