Question

why is carpet or curtains placed on the walls at movie theaters?
absorb sound to reduce transmission from one room 2 another
amplify sound with resonance
reflect sound to make transmission increase inside the room

Explanation:

In movie theaters, carpet or curtains on walls are used to absorb sound. Sound absorption materials like these reduce sound reflection and transmission, minimizing noise between rooms and improving audio quality inside the theater. Amplifying or reflecting sound would not be desired as they'd cause echoes or noise leakage, so absorbing sound to reduce transmission is the correct reason.

Answer:

The red option (absorb sound to reduce transmission from one room to another)