Assertion:Vestibular apparatus helps us in maintaining balance of body and posture.
Reason:Due to the arrangement of semicircular canals of vestibular apparatus, movement of head in any direction will stimulate sensory cells to maintain dynamic equilibrium.

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that the vestibular apparatus helps in maintaining the balance of the body and posture. This is true, as the vestibular apparatus is a critical component of the inner ear responsible for our sense of balance.

2. **Understanding the Reason**: The reason provided explains that the arrangement of the semicircular canals in the vestibular apparatus allows for the stimulation of sensory cells when the head moves in any direction, which helps maintain dynamic equilibrium. This is also true, as the semicircular canals are oriented in different planes and are sensitive to rotational movements.

3. **Connecting Assertion and Reason**: Since both the assertion and the reason are true, we need to determine if the reason correctly explains the assertion. The reason describes how the vestibular apparatus functions to maintain balance, directly linking the structure (semicircular canals) to its function (maintaining balance).

4. **Conclusion**: Both the assertion and the reason are true, and the reason is indeed 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 the assertion.

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