I think it would be D because the personal touch would be introducing you (the reader) to his son.
It is called an internal conflict. Meaning it isn't a physical problem, but it could still be a variety of things. Such as emotional or spiritual problems.
The answer would be the first choice or A. "Original ideas that are <em>not</em> your own."
Any piece of information that does not belong to you would require a citation, otherwise it would be considered <em>plagiarism. </em>B and C are incorrect because both of those things belong to you, and therefore don't require citation. D is also incorrect because a general fact doesn't belong to any one person. For example, if you wanted to include the information that dogs can't eat chocolate, that wouldn't require a citation because that is general knowledge that most people are aware of.
C....................................................