The power of accommodation in a human eye is the ability of the (i) to adjust its (ii).

Options

A. (1) pupil (ii) diameter
B. (i) pupil (ii) thickness
C. (i) lens (ii) focal length
D. (i) lens (ii) distance from the retina

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the power of accommodation in the human eye, specifically what it allows the eye to adjust.

2. **Identifying Key Components**: The human eye consists of various parts, but the two most relevant to this question are the lens and the focal length. The lens is responsible for focusing light onto the retina.

3. **Defining Power of Accommodation**: The power of accommodation refers to the eye's ability to change its focal length to see objects clearly at different distances. This is crucial for focusing on both near and far objects.

4. **Filling in the Blanks**:
- The first blank (i) refers to the part of the eye that adjusts. This is the **lens**.
- The second blank (ii) refers to what the lens adjusts. This is the **focal length**.

5. **Final Answer**: The power of accommodation in a human eye is the ability of the **lens** to adjust its **focal length**.

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