Assertion : Plantibodies are animal antibodies produced in plants
Reason : Plantibodies are just a theoretical concept

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Plantibodies are animal antibodies produced in plants."
- To analyze this, we need to understand what plantibodies are. Plantibodies are indeed antibodies that are produced in transgenic plants. These plants have been genetically modified to express genes that code for animal antibodies.

2. **Understanding the Reason**:
- The reason given is that "Plantibodies are just a theoretical concept."
- This statement needs to be evaluated against the current scientific understanding. Plantibodies are not merely theoretical; they have been successfully produced in transgenic plants and have practical applications.

3. **Evaluating the Truth of Assertion and Reason**:
- The assertion is true because plantibodies are real and are produced in plants that have been genetically engineered to express animal antibody genes.
- The reason is false because plantibodies are not just a theoretical concept; they have been demonstrated in practice.

4. **Conclusion**:
- Since the assertion is true and the reason is false, we can conclude that the correct answer to the question is that the assertion is true, but the reason is false.

### Final Answer:
- The assertion is true, and the reason is false.