Step 1: Understanding the Concept:
Targeted therapeutic drug classes and specific antiparasitic chemotherapy in veterinary medicine.
Step 2: Detailed Explanation:
Matching parasitic diseases in List I with specific chemotherapeutic agents in List II:
- A. Haemonchosis (Haemonchus contortus): Treated with broad-spectrum benzimidazoles $\rightarrow$ IV. Fenbendazole.
- B. Cestodiasis (Tapeworm infections): Specifically treated with isoquinoline pyrazines $\rightarrow$ III. Praziquantel.
- C. Babesiosis (Tick fever): Treated with aromatic diamidines $\rightarrow$ I. Diminazene aceturate.
- D. Coccidiosis (Eimeria spp.): Specifically treated with thiamine antagonist anticoccidials $\rightarrow$ II. Amprolium.
Matching sequence: A - IV, B - III, C - I, D - II.
Step 3: Final Answer:
Therefore, the correct matching is A - IV, B - III, C - I, D - II, corresponding to option (D).