Assertion (A) : Electrons have no thermal velocity in a conductor.
Reason (R ): Electron's direction of motion are randomly oriented.

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 also false

Explanation

To analyze the assertion and reason provided in the question, we will break down each statement and evaluate their validity step by step.

### Step 1: Understanding the Assertion (A)
**Assertion (A): Electrons have no thermal velocity in a conductor.**

- In a conductor, electrons are free to move and can carry an electric current. However, the term "thermal velocity" refers to the random motion of particles due to thermal energy.
- In a conductor, while electrons do possess a thermal motion due to thermal energy, this motion is not what is typically referred to when discussing the conduction of electricity. Instead, the net motion of electrons in a conductor under an electric field is what we consider.

### Step 2: Understanding the Reason (R)
**Reason (R): Electrons' directions of motion are randomly oriented.**

- This statement is true. In thermal equilibrium, the motion of electrons in a conductor is indeed random and isotropic. This means that, without an external electric field, the electrons move in all directions with no preferred direction.
- However, when an electric field is applied, the random motion of electrons is superimposed with a drift velocity in the direction of the field.

### Step 3: Evaluating the Assertion and Reason
- The assertion that "electrons have no thermal velocity in a conductor" is misleading. While the net motion of electrons under an electric field is what we observe as current, they do have thermal velocities due to their random motion.
- The reason provided is correct; electrons do have randomly oriented directions of motion in thermal equilibrium.

### Conclusion
- Both the assertion and the reason are not entirely correct when considered together. The assertion is incorrect, while the reason is correct.

### Final Answer
- The assertion (A) is **false** because electrons do have thermal velocities in a conductor. The reason (R) is **true** as electrons' directions of motion are indeed randomly oriented.