**Core Concept**
Rectal polyps are growths on the inner lining of the rectum, which can be benign or malignant. They often arise from the mucosal layer and can be associated with chronic inflammation and genetic predisposition. The most common type of rectal polyp is the adenomatous polyp.

**Why the Correct Answer is Right**
The correct answer is likely to be a symptom that is commonly associated with rectal polyps. Rectal polyps can cause bleeding, which is the most common presenting symptom. This is due to the erosion of the polyp into the lumen of the rectum or the overlying mucosa. The bleeding can range from occult to overt, and it may be visible on the surface of the stool or in the toilet bowl.

**Why Each Wrong Option is Incorrect**
* **Option A:** While abdominal pain can be a symptom of rectal polyps, it is not the most common presenting symptom.
* **Option B:** Constipation is not typically associated with rectal polyps unless the polyp causes a mechanical obstruction.
* **Option D:** Rectal polyps are not typically associated with weight loss.

**Clinical Pearl / High-Yield Fact**
It is essential to note that rectal polyps can be a precursor to colorectal cancer, especially if they are left untreated. Regular screening and surveillance are crucial in detecting and preventing colorectal cancer.

**Correct Answer:** B. Rectal polyps usually present with bleeding.