C because it's following a noun
We need the article to answer a question dont u think
Answer:
The aspect of languages contained in the sentence which speakers must avoid is <em>Incorrect Grammar.</em>
Explanation:
The sentence reads - "Fire<em><u> distinguishes</u></em> are generally colored red"
The correct sentence is - "Fire <em><u>extinguishers</u></em> are generally colored red"
Notice the error. The speaker says <em>distinguishers </em>instead of <em>extinguishers.</em>
The above is an example of grammatical error and must be avoided for sakes of clarity.
Cheers!
Hmm...an easier way to find a theme of the story would be either scheming through the story looking for clues or facts or read it.
I hope this answer helps.