Read the text. Circle the correct option (a-d).

3D printers

3D printers are a new kind of machine that can make everyday objects. They're amazing because they can produce different things in different materials, from cups and plates to plastic toys and even chocolate cakes! So how do they work?

First you design a 3D object on your computer, then you connect it to a 3D printer. Press "print" and watch it work. The printer makes the object in very thin layers, like the pages of a book - one on top of the other until you have a complete object.


What is the writer of the text doing?

a. giving an idea about the future of printers

b. describing an invention

c. giving a short history of an object

d. explaining different inventions