Which of these words doesn't make the sound of silence?
When you see a group of words that have a similar theme, it's easy to get hung up on their meaning. Instead,look for other ways to interpret the question asked of you.
For example, other than a very literal definition what else could "the sound of silence" be referring to?
Read each word out loud and pay attention to how they differ from each other. In particular, think about how each word is pronounced.
Think about what letters aren't pronounced.
Think carefully about the inscription again.
That's right, the answer is "Rest". All of the other options have silent letters.
Die Lösung ist: Rest.