Select the most appropriate word for the given group of words.

One who does not express himself freely

Introvert

The most appropriate word for the given group of words is introvert.

• Extrovert: a person who is outgoing and enjoys being around other people.
• Introvert: a person who is shy and prefers to spend time alone.
• Narcissist: a person who is excessively self-absorbed and has an inflated sense of their own importance.
• Lunatic: a person who is mentally ill or insane.

Introverts are typically more reserved and less likely to express themselves freely than extroverts. They may feel uncomfortable in large groups or social situations, and they may prefer to spend time alone or with close friends.