Assertion (A) In rabbit,caecum of large intestine is important for cellulose digestion
Reason ( R) Large intestine secretes an enzyme known as cellulase to digest cellulose in rabbit

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct but R is not the correct explation of A
C. A is false but R is true
D. A is true but R is false

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that in rabbits, the caecum of the large intestine is important for cellulose digestion. This is true because rabbits are herbivores and their diet consists mainly of plant material, which contains cellulose. The caecum serves as a fermentation chamber where bacteria help break down cellulose.

2. **Understanding the Reason (R)**:
- The reason states that the large intestine secretes an enzyme known as cellulase to digest cellulose in rabbits. This statement is false. While the caecum does play a role in cellulose digestion, it does not secrete cellulase. Instead, the digestion of cellulose is facilitated by mutualistic bacteria that reside in the caecum.

3. **Evaluating the Relationship Between A and R**:
- Since the assertion is true (the caecum is important for cellulose digestion in rabbits), but the reason is false (the large intestine does not secrete cellulase), we conclude that the assertion is correct but the reason is incorrect.

4. **Final Conclusion**:
- Therefore, the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- Assertion (A) is true, and Reason (R) is false.