**Core Concept**
The management of acute intestinal obstruction in a patient with a known malignancy, such as carcinoma of the descending colon, requires a careful approach to prevent complications and improve outcomes. The treatment of choice in this scenario must address the underlying cause of the obstruction, which in this case is likely the tumor.

**Why the Correct Answer is Right**
The correct answer is **C. Endoscopic stenting**. This is because endoscopic stenting is a minimally invasive procedure that can be used to relieve the obstruction caused by the tumor, allowing the bowel to return to normal function. This approach is particularly useful in patients with a known malignancy, as it avoids the need for surgical intervention and can help to preserve the patient's quality of life.

Endoscopic stenting involves the placement of a metal stent through the endoscope, which expands to relieve the obstruction. This procedure is usually performed under conscious sedation and can be done on an outpatient basis. The stent remains in place until the tumor grows or the patient's condition worsens, at which point it can be removed or replaced.

**Why Each Wrong Option is Incorrect**
**Option A:** **Surgical intervention** may be necessary in cases of intestinal obstruction, but it is not the first line of treatment in a patient with a known malignancy. Surgery carries significant risks, including infection, bleeding, and complications related to anesthesia.

**Option B:** **Conservative management** may be used in cases of intestinal obstruction, but it is not suitable for a patient with a known malignancy. Conservative management involves fluid resuscitation, bowel rest, and monitoring, but it does not address the underlying cause of the obstruction.

**Clinical Pearl / High-Yield Fact**
In patients with a known malignancy and acute intestinal obstruction, endoscopic stenting should be considered as a first-line treatment option. This approach can help to improve outcomes, reduce complications, and preserve the patient's quality of life.

**Correct Answer:** C. Endoscopic stenting