A newborn is hypermetropic by
**Core Concept**
Hypermetropia, also known as farsightedness, is a refractive error where distant objects are seen clearly, but near objects appear blurry. This condition occurs when the eyeball is too short or the cornea is too flat, resulting in an inability to focus light properly on the retina.
**Why the Correct Answer is Right**
The newborn's hypermetropia is due to the immaturity of the eyeball and the cornea. At birth, the eyeball is still developing and the cornea is relatively flat, leading to a refractive error. As the child grows, the eyeball elongates and the cornea becomes more curved, allowing light to focus properly on the retina and correcting the hypermetropia. This process is known as emmetropization.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the context of the question. The question specifically asks about the cause of hypermetropia in a newborn, and this option does not provide any information related to that.
**Option B:** This option is incorrect because it suggests that hypermetropia is caused by a structural abnormality in the eye, such as a cataract or retinal detachment. However, hypermetropia in a newborn is a normal and temporary condition caused by the immaturity of the eyeball.
**Option C:** This option is incorrect because it suggests that hypermetropia is caused by an underlying medical condition, such as diabetes or hypertension. However, hypermetropia in a newborn is not related to any underlying medical condition, but rather to the normal development of the eyeball.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that hypermetropia in a newborn is a normal and temporary condition that typically resolves as the child grows and develops. However, if the hypermetropia persists beyond the age of 2-3 years, it may indicate an underlying refractive error or other eye problem that requires further evaluation and treatment.
**Correct Answer: D.**