Dracunculiasis, also known as Guinea worm disease, is a parasitic infection that is caused by drinking contaminated water. Specifically, the disease is contracted by drinking water that contains tiny crustaceans called copepods that have been infected with Guinea worm larvae. Once ingested, the larvae mature into adult worms that can grow up to 3 feet long and cause painful symptoms such as blistering, fever, and nausea. Therefore, the correct answer is drinking contaminated water. It cannot be contracted through eating contaminated food, bathing in contaminated water or bites of blackfly.