Schistosomiasis, a common water-contact disease, is spread by which of the following?

Schistosomiasis spreads through cercaria, the free swimming larval stage of the blood fluke that bores through human skin in contaminated water.

Giardia is a protozoan that causes intestinal giardiasis spread by ingesting cysts, not by this skin penetrating larva.

E. coli is a bacterium linked to gut infections through contaminated food and water, unrelated to fluke larvae.

Amoeba causes amoebic dysentery through swallowed cysts, again a different transmission route.

The cercaria are released from freshwater snails that act as the intermediate host.

The disease is also known as bilharzia and is common where people contact infected fresh water.