**Core Concept**
The antemortem diagnosis of rabies involves the detection of the virus or its antigens in the patient's tissues, particularly in the nervous system. This can be achieved through various laboratory techniques, including staining methods that highlight the presence of viral antigens.

**Why the Correct Answer is Right**
The correct answer is **Negri Body staining**, which is a histopathological technique used to diagnose rabies. This staining method involves the use of a silver nitrate solution to highlight the presence of Negri bodies, which are characteristic inclusion bodies found in the cytoplasm of neurons infected with the rabies virus. The presence of Negri bodies in the brain tissue is a strong indicator of rabies infection.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not relate to the diagnosis of rabies. Other staining methods, such as hematoxylin and eosin (H&E) staining, may be used in the diagnosis of rabies, but they are not specific for the virus.
* **Option B:** This option is incorrect because it is not a staining method used in the diagnosis of rabies. Other laboratory techniques, such as PCR (polymerase chain reaction) or viral culture, may be used to diagnose rabies, but they are not staining methods.

**Clinical Pearl / High-Yield Fact**
The presence of Negri bodies in the brain tissue is a key diagnostic feature of rabies. However, it's worth noting that Negri bodies may not be present in all cases of rabies, especially in the early stages of the disease.

**Correct Answer:** C. Negri Body staining.