Examples for artificial magnets are
A. Bar magnet
B. Horseshoe magnet
C. Pot shaped and cylindrical magnets
D. All of the above

Hint: Magnets are a type of material which attract irons. Magnets are found naturally in lodestone (magnetite or iron ore). Also, magnets can be made from iron by adding some other elements such as cobalt, nickel or rare earth metals.

Complete answer:
Artificial magnets are the magnets in different shapes which are made from iron and its alloy.Artificial magnets are also known as hard magnets or permanent magnets.Bar magnet, horse shoe magnet, pot shaped and cylindrical magnets are examples of artificial magnets.The names of these magnets are given due to their shapes and sizes.

Hence, the correct option is D.

Additional information: The earth also has a magnetic field. The north pole of earth’s magnet lies in the southern hemisphere and south pole in the northern hemisphere. The pole of earth’s magnet near the geographical north pole of earth is called geomagnetic north pole. Similarly, the pole of earth’s magnet near the geographical south pole of earth is called the geomagnetic south pole. When a bar magnet is freely suspended horizontally, its north pole points towards the geomagnetic north pole of earth.

Note: All forms of magnets have two poles; north pole and south pole. For example, a bar magnet has two poles at the ends. Like poles repel and unlike poles attract each other.The region around a magnet which can attract irons towards the magnet is known as the magnetic field.