Which of the following is a correctly matched adjective noun pair?

The correct answer is Option 2 i.e. Restless - Restlessness

Explanation 

In the above question to identify the correctly matched adjective and noun, we need to know about an adjective and a noun.

• Adjective
  • ​​​​​A word that modifies a noun or a pronoun. 
  • Example: A tall boy
• ​Noun
  • ​A word that names people, place, things, and ideas
  • Example: Mike has bought a new car. Love is the most beautiful feeling.
• ​In the above options, the word Restless is an adjective as it can be used to modify a noun or a pronoun.
  • ​Example: A restless boy
• Similarly, the words Restlessly and Restive are also adjectives, and the word Restive is wrong. 
• In the above option, the word Restlessness is a noun.
  • Example: Restlessness is the inability to rest. 

​​Therefore Option 2 is the only pair with an adjective (Restless) and noun (Restlessness) making it the correct answer.