What is group 17 of the periodic table are known as?

Halogens

The correct answer is option 2. Halogens.

Group 17 of the periodic table is known as the "Halogens." These elements include fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). They are called halogens because they form salts when they react with metals, and the term "halogen" comes from the Greek words for "salt-forming." Therefore, the correct answer is Halogens.