Select the most appropriate synonym of the underlined word in the given sentence.
The cacophony in the theatre was too much for us.

The correct answer is noise.

Explanation:
The word cacophony refers to a harsh, discordant mixture of sounds or loud noise.

Let us analyze the given options:

1. silence: Refers to a complete absence of sound, which is the opposite (antonym) of cacophony.
2. smell: Refers to a scent or odor perceived by the nose, which is unrelated to sound.
3. noise: Refers to a sound, especially one that is loud, unpleasant, or causes disturbance. This closely matches the meaning of cacophony.
4. laughter: Refers to the sound or act of laughing, which does not capture the harsh and disturbing nature of cacophony.

Therefore, the most appropriate synonym for cacophony is noise.