Step 1: Understanding the Question:
This question tests knowledge of nutrient deficiency disorders in plants.
Step 2: Detailed Explanation:
Bitter pit (A): Caused by Calcium deficiency (II) (common in apple).
Little leaf (B): Caused by Zinc deficiency (I) (common in fruit crops).
Fruit cracking (C): Caused by Potassium deficiency (III).
Marginal burning of leaf (D): Caused by Boron deficiency (IV).
Thus, the correct matching is A-II, B-I, C-III, D-IV.
Step 3: Final Answer:
Thus, the correct answer is A-II, B-I, C-III, D-IV, which corresponds to option (C).
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