The answer is (A). I'm not a genius, but if there are smart things you can do (B,C,D) and then A is generic, the bad wording and lack of quotation, then that isn't recommended
The answer is D. Kindhearted
The root word for a geographer is Geography if I'm right
He is right it is complex
The valley later became a center of mining for borax.
because Borax was the center valley.
