Accommodation is maximum in:
**Core Concept**
Accommodation in the eye refers to the process of changing the optical power of the eye to maintain a clear image or focus on an object as its distance varies. This is achieved by changing the shape of the lens.
**Why the Correct Answer is Right**
The correct answer is the age group where the eye's ability to accommodate is at its maximum. Accommodation is primarily facilitated by the ciliary muscles, which contract to increase the curvature of the lens. This increases the refractive power of the lens, allowing the eye to focus on near objects. The maximum accommodation occurs in children and young adults due to the elasticity and strength of the ciliary muscles and the lens. However, with age, the elasticity of the lens and ciliary muscles decreases, reducing the ability to accommodate.
**Why Each Wrong Option is Incorrect**
**Option A:** Infancy - In infancy, the eye's ability to accommodate is still developing, and the lens and ciliary muscles are not yet fully formed.
**Option B:** Old age - In old age, the elasticity of the lens and ciliary muscles decreases, reducing the ability to accommodate.
**Option C:** Middle age - Middle age is a transitional phase where the eye's ability to accommodate begins to decline, but it is not at its maximum.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that presbyopia, a condition of reduced accommodation, typically begins in the early to mid-40s and is a natural consequence of aging.
**Correct Answer: C. Middle age. The eye's ability to accommodate is maximum in middle age, before the onset of presbyopia.**