A blacksmith uses . . . . . . . A. drill B. plane C. trowel D. bellows

The correct answer is: D. bellows

A blacksmith is a person who forges iron and other metals. They use a variety of tools to shape the metal, including bellows. Bellows are a device that is used to blow air into a fire, which makes the fire hotter. This allows the blacksmith to heat the metal to a high temperature so that they can shape it.

The other options are incorrect because they are not tools that are used by blacksmiths. A drill is a tool that is used to make holes in things. A plane is a tool that is used to smooth wood. A trowel is a tool that is used to spread mortar.