The correct option is D Anthony as well as Kiara came to help me with my shifting.
The given sentences are not related to each other, in the sense that they do not have any effect on each other. Such sentences require a cumulative conjunction that merely add them together. If the subject or verb is the same, they must not be repeated again.
Option A contains the cumulative conjunction "as well as", that connects the sentences together, by clubbing the subjects as a compound subject ("Anthony as well as Kiara") while retaining the rest of the sentence. Hence option A is correct.
Option B is incorrect because the conjunctions "neither...nor" aren't cumulative; they are alternative.
Similarly, the conjunction in D, "or", is also alternative. Hence option D is also incorrect.
Option C is incorrect because the conjunction, "but" is adversative, not cumulative.