**Core Concept**
Schistosomiasis, also known as snail fever, is a parasitic infection caused by blood flukes of the genus Schistosoma. The disease is prevalent in tropical and subtropical regions worldwide, with significant morbidity and mortality. Treatment of schistosomiasis aims to eliminate the parasite and prevent further transmission.

**Why the Correct Answer is Right**
The drug of choice for schistosomiasis is Praziquantel, a broad-spectrum anthelmintic that acts by binding to calcium channels on the surface of the parasite's muscle cells, leading to muscle contraction and ultimately, parasite death. Praziquantel is effective against all species of Schistosoma and is the recommended treatment by the World Health Organization (WHO). The mechanism of action of Praziquantel involves the disruption of the parasite's muscle function, leading to its expulsion from the host.

**Why Each Wrong Option is Incorrect**
* **Option A:** Oxamniquine is another anthelmintic used to treat schistosomiasis, but it is primarily effective against Schistosoma mansoni and is not the first-line treatment.
* **Option B:** Metronidazole is an antibiotic used to treat various infections, including amoebiasis and giardiasis, but it is not effective against schistosomiasis.
* **Option C:** Albendazole is an anthelmintic used to treat a range of parasitic infections, including hookworm and roundworm infections, but it is not the first-line treatment for schistosomiasis.

**Clinical Pearl / High-Yield Fact**
It is essential to note that Praziquantel is not effective against the eggs of the parasite, which can remain in the host's tissues for years. Therefore, repeated treatments may be necessary to eliminate the parasite completely.

**Correct Answer:** C. Praziquantel