Which of the following is an example of mercury poisoning?

Mercury poisoning is categorized as a heavy metal poisoning case because mercury is a toxic heavy metal that causes harmful effects when it enters the human body. This type of poisoning typically occurs through exposure to mercury through inhalation, ingestion, or skin contact. The symptoms can vary depending on the form of mercury involved (elemental, inorganic, or organic) and the extent of exposure.

Unlike food poisoning, which is typically caused by biological agents or toxins from contaminated food, mercury poisoning is specifically tied to the presence of this metal in the environment or through certain industrial processes. Likewise, chronic respiratory issues are not caused by mercury but can be attributed to other environmental factors or substances. An acidic substance reaction does not relate directly to mercury toxicity; rather, it involves chemical interactions of acids, which is not applicable in cases of heavy metal poisoning. Thus, identifying mercury poisoning as a case of heavy metal poisoning accurately reflects the nature of the substance and its toxic effects.