## Core Concept
The detection of poisons in an exhumed body, particularly in bones, involves understanding the persistence and deposition of various toxic substances in human tissues. Certain poisons can bind to or be stored in bones, allowing for their detection even after decomposition or exhumation.

## Why the Correct Answer is Right
The correct answer, **D. Arsenic**, is right because arsenic is well-known for its ability to accumulate in bones. When ingested, arsenic can substitute for phosphorus in bone tissue, leading to its deposition in bones. This property makes arsenic detectable in bones even years after exposure or death, which is why it's often sought in forensic investigations involving exhumed bodies.

## Why Each Wrong Option is Incorrect
- **Option A:** While certain volatile substances can be detected through other means, they are not characteristically stored in bones for later detection.
- **Option B:** Although some heavy metals can accumulate in bones, the specific context of detection in exhumed bodies makes some less relevant or less commonly associated with bone storage compared to arsenic.
- **Option C:** Certain organic compounds might be detectable in tissues, but similar to volatile substances, they are not specifically known for being stored in bones.

## Clinical Pearl / High-Yield Fact
A key point to remember is that **arsenic** is particularly notorious for its persistence in the environment and in human tissues, including bones. This persistence is why arsenic poisoning can sometimes be confirmed through analysis of hair, nails, or, relevantly, bones in exhumed bodies. This fact can be crucial in forensic pathology and toxicology.

## Correct Answer: D. Arsenic.