**Core Concept**
Anthrax is a zoonotic disease caused by the bacterium *Bacillus anthracis*. The disease can manifest in three main forms: cutaneous, inhalational, and gastrointestinal. The cutaneous form is the most common presentation, accounting for the majority of cases.

**Why the Correct Answer is Right**
The cutaneous form of anthrax typically occurs after a cut or scratch in the skin comes into contact with spores of *B. anthracis*. The spores germinate into vegetative cells, which produce toxins that cause local tissue damage and necrosis. The cutaneous form is usually self-limiting and can be treated with antibiotics if caught early.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the inhalational form of anthrax is a more severe and potentially life-threatening form of the disease, typically occurring after inhalation of spores.
**Option B:** This option is incorrect because the gastrointestinal form of anthrax is rare and usually occurs after ingestion of contaminated food or water.
**Option C:** This option is incorrect because it is not a recognized form of anthrax.

**Clinical Pearl / High-Yield Fact**
The cutaneous form of anthrax can be treated with antibiotics, but it is essential to start treatment within 24-48 hours of symptom onset to prevent severe complications.

**Correct Answer: C. Cutaneous anthrax is the commonest form of the disease.**