Step 1: Understanding the Question:
This question tests knowledge of the centers of origin of crops.
Step 2: Detailed Explanation:
Safflower (A): Originated in the Mediterranean and the Persian Gulf (III).
Sunflower (B): Originated in the Southwest United States and Mexico (I).
Soybean (C): Originated in China (IV).
Green gram (D): Originated in the Indian sub-continent (II).
Thus, the correct matching is A-III, B-I, C-IV, D-II.
Step 3: Final Answer:
Thus, the correct answer is A-III, B-I, C-IV, D-II, which corresponds to option (C).
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