**Core Concept**
Echinococcosis, also known as hydatid disease, is a parasitic infection caused by the Echinococcus tapeworm. The treatment of echinococcosis involves antiparasitic medications that target the parasite's life cycle.

**Why the Correct Answer is Right**
The drug commonly used in the treatment of echinococcosis is albendazole, a benzimidazole antiparasitic agent. Albendazole works by inhibiting the parasite's microtubule function, leading to the disruption of its life cycle and ultimately, the death of the parasite. This mechanism of action is crucial in treating echinococcosis, especially in cases where surgical intervention is not feasible.

**Why Each Wrong Option is Incorrect**
**Option A:** Praziquantel is an antiparasitic agent used to treat schistosomiasis and other fluke infections, but it is not the primary treatment for echinococcosis.
**Option B:** Ivermectin is an antiparasitic agent used to treat a range of parasitic infections, including onchocerciasis and strongyloidiasis, but it is not effective against echinococcosis.
**Option C:** Metronidazole is an antibiotic used to treat bacterial and protozoal infections, but it is not used to treat echinococcosis.

**Clinical Pearl / High-Yield Fact**
It's essential to note that albendazole is often used in combination with surgical intervention to treat echinococcosis, especially in cases where the disease is widespread or has caused significant organ damage.

**Correct Answer:** C. Albendazole