**Core Concept**
During the ovulation phase, a surge in luteinizing hormone (LH) triggers the resumption of meiosis in the oocyte. This is a critical event that prepares the ovum for release from the antral follicle. The resumption of meiosis is a complex process, involving the breakdown of the nuclear envelope and the separation of the chromosomes.

**Why the Correct Answer is Right**
The correct answer, "Stimulation of the arrested meiotic division of the ovum," accurately describes the physiological event that occurs during ovulation. The surge in LH causes the oocyte to exit the diplotene stage of prophase I, allowing it to proceed through meiosis II. This process is essential for the release of a mature ovum from the follicle. The LH surge also triggers the rupture of the follicle, resulting in ovulation.

**Why Each Wrong Option is Incorrect**
**Option A:** Increase in inhibin A level is incorrect because inhibin A levels decrease during the LH surge, allowing FSH to continue stimulating follicular growth.

**Option B:** FSH induces steroidogenesis in granulosa cells in the secretory phase, not during ovulation. FSH stimulates the production of estradiol and progesterone in the follicular phase, but LH is responsible for steroidogenesis during the luteal phase.

**Option C:** Activin levels actually decrease during the LH surge, as the follicle-stimulating hormone (FSH) receptors are downregulated, leading to a decrease in activin production.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the LH surge is a critical event in ovulation, triggering the resumption of meiosis and follicular rupture. This process is often used as a marker for ovulation in fertility treatments and reproductive endocrinology.

**Correct Answer:**
✓ Correct Answer: D. Stimulation of the arrested meiotic division of the ovum