**Core Concept**
Retinoblastoma is a malignant tumor of the retina, primarily affecting children under the age of 5. It is a genetic disorder characterized by the mutation of the RB1 gene, which plays a crucial role in regulating cell growth and division.

**Why the Correct Answer is Right**
The correct answer, **D. More common in negroes than whites**, is incorrect because retinoblastoma is actually more common in Caucasians (whites) than in African Americans (negroes). The incidence of retinoblastoma varies geographically, with higher rates observed in developed countries. The disease is rare in populations of African descent, with an incidence of approximately 1 in 20,000 live births, compared to 1 in 15,000 to 1 in 20,000 in Caucasians.

**Why Each Wrong Option is Incorrect**
**Option A:** Retinoblastoma is indeed the most common intraocular tumor of childhood, but this option is not relevant to the question about incidence.

**Option B:** The incidence of retinoblastoma is reported to be approximately 1 in 15,000 to 1 in 20,000 live births, which aligns with the provided range of 1 in 14,000 to 34,000.

**Option C:** Retinoblastoma does not exhibit a significant sex predisposition, making this option true.

**Clinical Pearl / High-Yield Fact**
Retinoblastoma is a hereditary tumor, and patients with a family history of the disease are at increased risk. The RB1 gene is a tumor suppressor gene, and mutations in this gene lead to uncontrolled cell growth and tumor formation.

**Correct Answer:**
✓ Correct Answer: D. More common in negroes than whites