Select the option that can be used as a one-word substitute for the given group of words.

Someone who is reserved and shy

Introvert

The word that can be used as a one-word substitute for "someone who is reserved and shy" is introvert.

• Social means someone who enjoys being around people.
• Extrovert means someone who is outgoing and enjoys being around people.
• Recessive means tending to avoid attention or social interaction.
• Introvert means someone who is shy and prefers to spend time alone.

Introvert is the most appropriate word for the given group of words because it specifically refers to someone who is shy and prefers to spend time alone. It is derived from the Latin word introversus, meaning "turned inward."