Role of enamel is to

Enamel is the outermost layer of the tooth and is the hardest substance in the human body. It is secreted by ectodermal cells called ameloblasts. Enamel forms the hard chewing surface of the crown of the tooth. It protects the tooth from mechanical forces during chewing and biting.

(1) The neck connects the crown with the root.

(3) Formation of bolus involves mixing food with saliva to create a soft, moist mass that can be easily swallowed.
This process occurs in the mouth and involves the action of the tongue and other structures, but enamel is not directly involved in this process.

(4) Enamel also provides a protective outer layer for the teeth, maintaining their shape and integrity while resisting wear
and tear. This is also a correct option.