Assertion: Two particles of different mass, projected with same velocity at same angles. The maximum height attained by both the particle will be same.
Reason: The maximum height of projetile is independent of particle mass.

Options

A. Statement-I is true, Statement-II is true, Statement-II is correct explanation for Statement-I
B. Statement-I is true, Statement-II is true, Statement-II is NOT a correct explanation for Statement-I
C. Statement-I is true, Statement-II is false
D. Statement-I is false, Statement-II is true.

Explanation

To solve the question, we need to analyze the assertion and reason provided:

**Assertion:** Two particles of different mass, projected with the same velocity at the same angles, will attain the same maximum height.

**Reason:** The maximum height of a projectile is independent of the particle's mass.

### Step-by-Step Solution:

1. **Understanding Projectile Motion:**
- In projectile motion, the maximum height (H) attained by a projectile is determined by its initial velocity (u), the angle of projection (θ), and the acceleration due to gravity (g).

2. **Formula for Maximum Height:**
- The formula for the maximum height (H) is given by:
\[ H = \frac{u^2 \sin^2 \theta}{2g} \]
- Here, \( u \) is the initial velocity, \( \theta \) is the angle of projection, and \( g \) is the acceleration due to gravity.

3. **Analyzing the Given Conditions:**
- The assertion states that two particles of different masses are projected with the same initial velocity (u) and at the same angle (θ).
- Since both particles are projected with the same initial velocity and angle, we can conclude that the terms \( u \) and \( \theta \) are the same for both particles.

4. **Independence from Mass:**
- In the formula for maximum height, there is no term that includes mass (m). This indicates that the maximum height attained by a projectile does not depend on its mass.
- Therefore, regardless of the mass of the particles, if they are projected with the same velocity and angle, they will reach the same maximum height.

5. **Conclusion:**
- Since the maximum height is independent of mass, both particles will indeed reach the same maximum height when projected under the given conditions.
- Thus, both the assertion and the reason are true, and the reason correctly explains the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is the correct explanation for the assertion.