An echo chamber is... * 1.a physical room that bounces sound off the wall 2.a place to gather diverse ideas 3.a marketplace where ideas and posts compete for popularity 4.a self-imposed set of conditions in which you are only exposed to ideas and opinions aligned to your own

The correct option is;

1. A physical room that bounces sound off the wall

Explanation:

In Engineering,  An echo chamber is a room which is used to produce a persistent repetition of a sound after the initial sound is made mainly with the intention of recording purpose

Echo chambers are used in radio programming for sound cave or large room sound effects such that the reverberations are picked up by microphones which provides amplification

Current day echo chambers are achieved by electronic sound effects functions present in modern sound equipment, however, physical echo chambers, such as the famous Capitol Studios echo chambers are still in use.

primary groups shape your individual development

explanation: