Slangs in a language are usually ephemeral in nature.

Answer: Option A

Transient : lasting only for a short time; impermanent.
Customary : according to the customs or usual practices associated with a particular society, place, or set of circumstances.
Necessary : needed to be done, achieved, or present; essential.
Obvious : easily perceived or understood; clear, self-evident, or apparent.
Ephemeral : lasting for a very short time.

Synonym of Ephemeral is Transient