For number 12 to 15, choose the most suitable words to fill in the blanks.

    Sharks are (12) ____ fish that have been around long before the dinosaurs existed. They live in waters all over the world, in every ocean, and even in some rivers and lakes.

   There (13) ____ many different species of shark that range in size of a person's hand to bigger than a bus. Fully-grown sharks range in size from 7 inches (18 cm) long (the spined pygmy shark), up to 50 feet (15 m) long (the whale shark). Most sharks are intermediate in size, and about the same size as people, 5-7 (1,5-2,1 m) long. Half of the 368 species are under 39 inches (1 m) long.

    Sharks (14) ____  a variety of body shapes. Most sharks have streamlined, torpedo-shaped bodies that glide easily through the water. Some bottom dwelling sharks such as the angel sharks have flattened bodies that allow them to hide in the sand of the ocean bed. Some sharks have an elongated body (15) ____  such as cookie cutter sharks. Saw sharks have elongated snouts, thresher sharks have a tremendously elongated upper tail fin  which they use to stung prey, and hammerheads have extraordinarily wide heads. The goblin shark has a large, pointed protuberance on its head.

The correct answer for number 15 is ....