Select the most appropriate meaning of the following idiom.

The acid test

A fact, event or situation that proves something

The most appropriate meaning of the idiom "the acid test" is >A fact, event or situation that proves something.<

This idiom comes from the use of acid to test the purity of gold or silver. If the metal was pure, it would not react with the acid. However, if the metal was impure, it would react with the acid and change color.

In the figurative sense, the acid test is a situation or event that will prove someone's true character or worth. It is often used to describe a difficult or challenging situation that will test someone's abilities or resolve.

For example, you might say that a job interview is the acid test for a candidate's skills and knowledge. Or, you might say that a war is the acid test of a nation's strength and resolve.

The other options are not correct.

• Throwing acid on someone’s face is a violent act and is not the meaning of the idiom "the acid test."
• A critical situation or crisis is not the same as the acid test.
• An unpleasant or offensive test is not the same as the acid test.