I believe the answer would be Bill Gates. An appositive is a noun that renames a noun right beside it. In this case, "Bill Gates" is renaming "One of the richest men in the world."
The fourth one is the answer
The speaker is disappointed.
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Answer:</h2><h2>
A x b's daughter</h2><h2>
B x C's mum</h2><h2>
D x C's bro</h2>
<h2 /><h2> D and A are Siblings: Because, A and C have one mum...</h2>
