Arrange the dairy chain from source to derived products: Items: 1. curd 2. grass 3. butter 4. milk 5. cow Choose the correct production/derivation sequence.

Introduction / Context:
This sequence traces how a primary input (fodder) leads to dairy products through biological production and processing steps.

Given Data / Assumptions:

• 2 = Grass (fodder).
• 5 = Cow (producer of milk).
• 4 = Milk (primary output).
• 3 = Butter (derived from milk/cream).
• 1 = Curd (can be derived from milk as well; here we place it after butter to fit the intended single chain).

Concept / Approach:
Start with input feed → animal → primary product → processed derivatives. While both curd and butter derive from milk, the single linear chain expected by such questions typically lists major processed products after milk; we finalize with curd to complete the given set.

Step-by-Step Solution:

Verification / Alternative check:
Either butter or curd may be interchanged in real workflows (both from milk), but the provided correct option reflects a common textbook chain.

Why Other Options Are Wrong:

• Starting with cow or milk ignores the fodder cause.
• Placing curd before milk contradicts derivation.

Common Pitfalls:
Forgetting that animal nutrition precedes production; mixing up parallel derivatives into a single linear order.

Final Answer:
2, 5, 4, 3, 1