Step 1: Understanding the Concept:
Every crop has specific "key pests" that cause significant economic damage. Identifying these associations is fundamental to Integrated Pest Management (IPM).
Step 3: Detailed Explanation:
1. Rice (A): The Gundhi bug (Leptocorisa acuta) is a major pest during the milking stage, sucking sap from developing grains. (Matches IV)
2. Sesame (B): The Capsule borer/Leaf webber (Antigastra catalaunalis) is the most destructive pest of til/sesame. (Matches I)
3. Cotton (C): The Pink bollworm (Pectinophora gossypiella) is a notorious pest that destroys the lint and seeds inside the boll. (Matches II)
4. Chickpea (D): While the pod borer is most famous, the White grub (Holotrichia spp.) is a significant soil-borne pest affecting chickpea roots in sandy soils. (Matches III)
Step 4: Final Answer:
The correct matches are A-IV, B-I, C-II, D-III.