Select the most appropriate meaning of the given idiom.
Once in a blue moon

Correct option is C

Once in a blue moon – something that happens very rarely.

Explanation:
The idiom "once in a blue moon" is used to describe an event or occurrence that happens infrequently. A "blue moon" is a rare astronomical event, hence the association with rarity.

Use in a sentence:
We go out for dinner only once in a blue moon, usually on special occasions.

Similar idioms:

1. Once in a lifetime – something that happens only one time in a person’s life or extremely rarely.
   Example: Visiting Antarctica was a once-in-a-lifetime experience.

2. Few and far between – something that happens infrequently or is hard to find.
   Example: Good job opportunities in that town are few and far between.