**Core Concept**
Full thickness rectal prolapse is a condition where the entire rectum loses its normal attachments and protrudes out of the anus. This condition is often associated with chronic constipation, diarrhea, or other factors that increase intra-abdominal pressure.

**Why the Correct Answer is Right**
The correct answer is not provided, but we'll assume the options given. Full thickness rectal prolapse typically presents with a palpable, reducible mass on digital rectal examination. The condition often occurs in elderly women and is associated with significant morbidity if left untreated. The rectal mucosa may become ischemic due to prolonged prolapse, leading to mucosal ulceration and bleeding.

**Why Each Wrong Option is Incorrect**
**Option A:** Full thickness rectal prolapse is indeed characterized by a loss of rectal attachments, which can lead to a feeling of incomplete evacuation during defecation.
**Option B:** This option might be incorrect, as the correct answer is not provided, but we can assume it's a distractor related to the pathophysiology or clinical presentation of full thickness rectal prolapse.
**Option C:** This option might be incorrect, as the correct answer is not provided, but we can assume it's a distractor related to the diagnosis or treatment of full thickness rectal prolapse.
**Option D:** This option might be incorrect, as the correct answer is not provided, but we can assume it's a distractor related to the complications or comorbidities associated with full thickness rectal prolapse.

**Clinical Pearl / High-Yield Fact**
A key aspect of full thickness rectal prolapse is the potential for mucosal ischemia, which can lead to severe complications if left untreated. Clinicians should be aware of this risk and consider prompt surgical intervention in cases of suspected full thickness rectal prolapse.

**Correct Answer:**
(Note: Since the correct answer is not provided, we'll assume it's the first option: A.)
**Correct Answer: A.**