Okay, so the question is about identifying the type of poisoning that causes a 'red velvety' stomach mucosa. The options aren't provided, but the correct answer is supposed to be one of the common poisons. Let me think.

First, I need to recall what causes such a gastric appearance. The term 'red velvety' makes me think of inflammation or damage to the stomach lining. Common poisons that affect the stomach... Maybe something like arsenic? Wait, arsenic poisoning can cause gastrointestinal symptoms, but does it lead to a red velvety mucosa? Or maybe something else like corrosive substances, like strong acids or alkalis. Wait, but corrosive substances usually cause necrosis and sloughing, not a velvety red look.

Another possibility is lead poisoning. Lead can cause abdominal colic and constipation, but does it affect the mucosa like that? Not sure. Mercury? Mercury vapor can cause oral and GI symptoms, but again, not sure about the mucosal appearance.

Wait, there's a condition called "strawberry tongue" in scarlet fever, but that's in the mouth. For the stomach, maybe it's related to a specific chemical. Oh! I remember that in some cases, like with certain heavy metals or chemicals, the stomach lining can become inflamed and have a red, velvety appearance.

Wait, arsenic poisoning is known to cause a red, swollen, and velvety stomach mucosa. That's a classic sign. So arsenic would be the answer. Let me confirm. Arsenic trioxide, for example, when ingested, causes acute poisoning with severe gastritis. The mucosa becomes hyperemic, swollen, and has a red velvety appearance. That's a key point.

So the correct answer here is arsenic. The other options might include other poisons like lead, mercury, or maybe something like potassium permanganate. Let me think about the other options. Lead poisoning typically causes abdominal pain and constipation, but not the same mucosal changes. Mercury might cause a metallic taste and oral ulcers. Potassium permanganate is a strong oxidizing agent; ingestion would cause burns and necrosis, not a velvety red look. So the wrong options would be other heavy metals or corrosive substances.

Therefore, the answer is arsenic. The clinical pearl here is that arsenic poisoning is associated with a red velvety stomach mucosa, which is a key diagnostic sign. Students should remember this classic appearance for exams.

**Core Concept**
The "red velvety" appearance of gastric mucosa is a classic histopathological finding in **arsenic poisoning**. Arsenic induces acute gastritis, leading to hyperemia, edema, and superficial erosion of the gastric lining, creating this characteristic appearance. This is part of the broader systemic toxicity of arsenic trioxide, a heavy metal poison.

**Why the Correct Answer is Right**
Arsenic poisoning causes severe inflammation of the gastrointestinal tract. The toxin binds to sulfhydryl groups in proteins, disrupting cellular metabolism and causing direct mucosal damage. This results in a **hyperemic ("red"), swollen ("velvety") gastric mucosa** with superficial erosions. The "velvety" texture arises from edema and exudate, while the redness reflects capillary

✓ Correct Answer: B. Arsenic