The sentence which uses correct punctuation is C. In time, of course, all issues get resolved, but not necessarily in the way you would like.
In A, the comma before <em>he was concerned </em>should be a dash. In B, there should be a colon before <em>a flashlight, </em>not a semi colon. In D, there should be a comma before <em>yet, </em>and not a colon.
It’s because the pronunciation is technically a ‘y’ sound, and even though y is sometimes considered a vowel, ‘an’ is not used in front of words that start with the ‘y’ sound.
To convey inner thoughts of the characters to the reader, or to have characters communicate to each other to help the reader gain information upon each of their personalities, inner thoughts, and their views upon the world/setting/plot.
Could you give more context?
