**Core Concept**
Cowhorn forceps, also known as Pean forceps, are a type of surgical instrument used to grasp and retrieve foreign bodies, such as teeth, or to extract impacted objects from the body. The unique design of the forceps allows for secure grip and control during the extraction process.

**Why the Correct Answer is Right**
The cowhorn forceps are specifically designed to grasp and extract impacted teeth, particularly those that are difficult to access due to their location or the surrounding anatomy. The curved shape of the forceps allows for precise placement and grip on the tooth, while the beaks of the forceps provide a secure hold. This enables the dentist or surgeon to carefully extract the tooth without causing further damage to the surrounding tissues.

**Why Each Wrong Option is Incorrect**
**Option A:** This is incorrect because cowhorn forceps are not typically used for extracting stones or kidney stones, which require specialized instruments like nephroscopes or ureteroscopes.
**Option B:** This is incorrect because cowhorn forceps are not used for grasping or extracting foreign bodies like bullets or shrapnel, which require specialized forensic or surgical instruments.

**Clinical Pearl / High-Yield Fact**
Cowhorn forceps are a crucial instrument in dental and maxillofacial surgery, and their use requires great skill and precision to avoid damaging surrounding tissues. It's essential to choose the correct instrument for the specific procedure to ensure successful extraction and minimize complications.

**Correct Answer:** C. impacted teeth