**Core Concept**
The question is testing the understanding of the effects of corticosteroids on the eye, specifically on the lens. Corticosteroids are known to cause cataracts, and the early changes in corticosteroid-induced cataract are characterized by specific alterations in the lens.

**Why the Correct Answer is Right**
Corticosteroids can cause cataracts due to their effect on the lens fibers. The early changes in corticosteroid-induced cataract are typically seen in the central posterior subcapsular (CPS) region of the lens. This is because the CPS region is more susceptible to the effects of corticosteroids, which can lead to the accumulation of proteins and the formation of cataracts. The pathogenesis of corticosteroid-induced cataracts involves the inhibition of the enzyme, alpha-crystallin, which is responsible for maintaining the transparency of the lens.

**Why Each Wrong Option is Incorrect**
**Option A:** Not applicable, as this is the correct answer.
**Option B:** Anterior cortical lens changes are not the typical early changes seen in corticosteroid-induced cataracts. These changes are more commonly associated with other types of cataracts, such as age-related cataracts.
**Option C:** Nuclear changes are also not typically seen in the early stages of corticosteroid-induced cataracts. Nuclear changes are more commonly associated with aging or other types of cataracts.
**Option D:** Diffuse lens changes are not a characteristic feature of corticosteroid-induced cataracts. These changes are more commonly associated with other types of cataracts, such as age-related cataracts.

**Clinical Pearl / High-Yield Fact**
Corticosteroids can cause cataracts in as little as 6-8 weeks after initiation of treatment, making regular eye exams essential for patients on long-term corticosteroid therapy.

**✓ Correct Answer: A. Central posterior subcapsular lens changes**