Question

polish off any remaining tarnish with the brass cleaner. source: washington post. in the sentence above, tarnish has the same or almost the same meaning as: stain dust soap flour

Explanation:

The word "tarnish" refers to a thin layer of oxide on a metal surface, which is similar in meaning to a "stain" that discolors a surface. Dust is fine particles, soap is a cleaning agent, and flour is a powder - none of these are similar to tarnish in meaning.

Answer:

A. stain