Final answer:
The correctly punctuated sentence is option C, using commas for natural pauses, ellipsis points to indicate a change in thought and an exclamation mark for emphasis.
Step-by-step explanation:
The sentence with correct punctuation from the provided options is C) "Yes, can you tell him that Julia stopped by... actually, never mind... don't tell him anything!" This version correctly uses commas after 'Yes' and 'actually' to reflect natural pauses in the speech, as well as ellipsis points to indicate a trailing off or shift in thoughts before 'never mind'. It also ends with an exclamation mark, adding emphasis to the speaker's final decision to not relay the message.
When punctuating a sentence, it is crucial to consider elements such as natural pauses, shifts in thought, and the finality or emphasis at the end of a statement. Punctuation marks like commas, ellipses, and exclamation points help convey these aspects of spoken language in written form, enhancing the clarity and emotional tone of the sentence.