Assertion (A): Rough ER is in continuation with nuclear membrane.
Reason (R ): DNA controls the protein synthesis in rough ER.

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**: The assertion states that the Rough Endoplasmic Reticulum (Rough ER) is in continuation with the nuclear membrane. This is true because the Rough ER is indeed an extension of the nuclear envelope, which surrounds the nucleus of the cell.

2. **Understanding the Reason (R)**: The reason states that DNA controls the protein synthesis in the Rough ER. This is also true because DNA, located in the nucleus, contains the instructions for protein synthesis. The Rough ER, with its ribosomes, is the site where this protein synthesis occurs based on the instructions provided by mRNA, which is transcribed from DNA.

3. **Evaluating the Relationship**: The assertion is true, and the reason is also true. Furthermore, the reason correctly explains the assertion because the Rough ER's role in protein synthesis is directly linked to the instructions provided by DNA.

4. **Conclusion**: Both the assertion and the reason are true, and the reason is the correct explanation of the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

**Final Answer**: Both assertion and reason are true, and reason is the correct explanation of assertion.

---