Select the most appropriate meaning of the given idiom.

Water under the bridge

Anything from the past that isn't significant or important anymore.

The most appropriate meaning of the idiom "water under the bridge" is (2) Anything from the past that isn't significant or important anymore.

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

• To be very sick is to be ill.
• A paranormal sense that allows you to communicate with the dead is called mediumship.
• Someone else who takes the blame is called a scapegoat.

The idiom "water under the bridge" is used to describe something that has happened in the past and that is no longer relevant or important. It is often used to suggest that it is time to move on from something and not dwell on it.