Explanation

Answer:

C

ERSATZ: Manufactured or used as an alternative to others (of the product) and is usually inferior.

 Artificial: Manufactured or used as an alternative to others (of the product) and is usually inferior.

 Chaotic: In a condition of entire confusion and disorder.

Impromptu: Without planning, organizing, rehearsals

 Vague:   an  indefinite, uncertain, or unclear thing, character, or meaning