**Core Concept**
Ulcerative colitis (UC) is a type of inflammatory bowel disease characterized by chronic inflammation of the colon, which increases the risk of colorectal cancer. The risk of malignancy in UC is related to the extent and duration of the disease, with the highest risk seen in patients with pancolitis and a long disease duration.

**Why the Correct Answer is Right**
The correct answer is D. Evenly distributed, because the risk of malignancy in ulcerative colitis is not evenly distributed throughout the colon. The risk is highest in the rectum and decreases proximally. The correct answer C, "Poor prognosis as compared to sporadic," is actually the false statement. Patients with colorectal cancer arising in the setting of ulcerative colitis have a similar prognosis to those with sporadic colorectal cancer, and may even have a better prognosis due to earlier diagnosis.

**Why Each Wrong Option is Incorrect**
**Option A:** The mean age of patients with ulcerative colitis and malignancy is actually higher than 30 years, often in the 50s or 60s.
**Option B:** Anaplastic cancers are not common in ulcerative colitis; in fact, the majority of colorectal cancers in UC are adenocarcinomas.
**Option C:** As mentioned earlier, patients with colorectal cancer arising in the setting of ulcerative colitis have a similar prognosis to those with sporadic colorectal cancer.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the risk of malignancy in ulcerative colitis increases with the extent and duration of the disease, and patients with pancolitis and a long disease duration are at highest risk.

**✓ Correct Answer: D. Evenly distributed**