Select the most appropriate meaning of the given idiom.

Wet blanket

One who spoils other people’s fun

The most appropriate meaning of the idiom "wet blanket" is one who spoils other people's fun. It is an informal expression that refers to someone who is negative, boring, or unenthusiastic, and who tends to dampen the spirits of others. The idiom is thought to have originated in the 19th century, and it is believed to be a reference to the way that a wet blanket would extinguish a fire.

The other options for the meaning of the idiom are incorrect. One who acts stupidly does not spoil other people's fun. One who is frequently ill does not spoil other people's fun. One who cannot be trusted does not spoil other people's fun.