Assertion (A): Electric field inside a hollow conducting sphere is zero.
Reason (R ): Charge is present on the surface of conductor.

Options

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

Explanation

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

**Step 1: Understanding the Assertion (A)**
The assertion states that "Electric field inside a hollow conducting sphere is zero."
- According to electrostatic principles, when a conductor is in electrostatic equilibrium, the electric field inside the conductor (and hence inside a hollow conducting sphere) is indeed zero. This is because any excess charge on a conductor redistributes itself on the surface, leading to no electric field within the hollow region.

**Step 2: Understanding the Reason (R)**
The reason states that "Charge is present on the surface of the conductor."
- In a hollow conducting sphere, when a charge is placed on it, the charge resides entirely on the outer surface of the sphere. Inside the hollow part of the sphere, there is no charge present. The absence of charge in the interior leads to the conclusion that the electric field inside is zero.

**Step 3: Linking Assertion and Reason**
Now we need to determine if the reason correctly explains the assertion.
- The reason provided indicates that the charge is on the surface, which leads to the conclusion that there is no charge inside the hollow sphere. According to Gauss's law, since there is no charge enclosed within a Gaussian surface inside the hollow sphere, the electric field must be zero.

**Step 4: Conclusion**
Both the assertion and the reason are true, and the reason correctly explains why the electric field inside the hollow conducting sphere is zero. Therefore, the correct answer is that both A and R are true, and R is the correct explanation of A.

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