Select the most appropriate meaning of the given idiom.

Keep someone at arm's length

Avoid being friendly with someone

The most appropriate meaning of the given idiom "keep someone at arm's length" is (4) Avoid being friendly with someone.

The idiom "keep someone at arm's length" means to avoid becoming too friendly or involved with someone. It is often used to describe someone who is wary of others or who does not want to get too close to anyone.

The other options do not fit the meaning of the idiom.

• Restrict someone to a small space to stand means to prevent someone from moving around freely.
• Allow someone to talk only from a distance means to allow someone to communicate with you but not to get too close.
• Make someone stay outside means to force someone to remain outside a building or a room.