'Dear Sir' in the formal letter is ____.

The correct answer is Option (2) → Salutation

The salutation is the greeting with which a letter begins, written just before the body. In a formal letter it is usually "Sir", "Madam", "Dear Sir" or "Dear Madam".
Example: She began her application with the salutation "Respected Madam".

Why the Other Options are Incorrect?

Option 1: The address of the sender — Incorrect. The sender's address is written at the top of the letter, above the date; "Dear Sir" is a greeting, not an address.

Option 3: Represents emotions — Incorrect. A formal letter keeps a polite, impersonal tone; "Dear Sir" is a set form of greeting, not an expression of feeling.

Option 4: Complimentary close — Incorrect. The complimentary close is the polite ending such as "Yours faithfully", written at the end of the letter.