[A]: Hanstein's dermatogen is not eqyivalent to Haberlandt's Protoderm.
[R]: Histogen theory has been proposed by Schemidt

Options

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

Answer

To analyze the assertion and reason provided in the question, we can break it down into steps:

### Step 1: Understanding the Assertion
The assertion states that "Hanstein's dermatogen is not equivalent to Haberlandt's protoderm."

- **Explanation**: Hanstein's dermatogen refers to the outermost layer of the primary meristematic tissue in plants, which is responsible for the formation of the epidermis. On the other hand, Haberlandt's protoderm is also an outer layer but is defined in a different context and classification system. Therefore, they are not equivalent.

### Step 2: Understanding the Reason
The reason states that "Histogen theory has been proposed by Schemidt."

- **Explanation**: The histogen theory was actually proposed by Hanstein in 1870, not Schemidt. This theory classifies the primary meristem into three layers: dermatogen, periblem, and plerome. Thus, the statement regarding Schemidt is incorrect.

### Step 3: Conclusion
Based on the analysis:
- The assertion (A) is true because Hanstein's dermatogen is indeed not equivalent to Haberlandt's protoderm.
- The reason (R) is false because the histogen theory was proposed by Hanstein, not Schemidt.

### Final Answer
The correct answer is:
- A is true, and R is false.

---