Select the most appropriate meaning of the given idiom.

On the wane

On the decline

The most appropriate meaning of the given idiom is (3) On the decline.

The idiom "on the wane" means to be decreasing or becoming weaker. It is often used to describe something that is no longer as popular or as important as it once was.

The other options do not fit the meaning of the idiom.

• On the way means something that is moving or progressing towards a destination.
• On the top means something that is at the highest point or level.
• On the rise means something that is increasing or becoming stronger.