Step 1: Identify the disease in question.
The disease is Sleeping Sickness, also known as Human African Trypanosomiasis (HAT).
Step 2: Recall the causative agents of common diseases.
Sleeping Sickness (Human African Trypanosomiasis): This disease is caused by protozoan parasites of the genus Trypanosoma. Specifically, Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense are the subspecies responsible for the disease in humans. It is transmitted by the tsetse fly.
SARS: SARS (Severe Acute Respiratory Syndrome) is caused by a virus (SARS-CoV), not bacteria.
Staphylococcus Bacteria: Staphylococcus bacteria cause various infections, including skin infections (like boils, impetigo), food poisoning, and more serious conditions like sepsis, but not sleeping sickness.
Protozoan Leishmania: Leishmania protozoans cause Leishmaniasis, a disease with different forms affecting the skin, mucous membranes, or internal organs, transmitted by sandflies. It is distinct from sleeping sickness.
Step 3: Evaluate the given options.
(1) Protozoan Trypanosoma: This is the correct causative agent for sleeping sickness.
(2) SARS Bacteria: Incorrect; SARS is viral.
(3) Staphylococcus Bacteria: Incorrect; Staphylococcus causes different types of bacterial infections.
(4) Protozoan Leishmania: Incorrect; Leishmania causes Leishmaniasis.
Step 4: Conclude the correct causative agent.
Sleeping sickness is caused by the Protozoan Trypanosoma.
(1) Protozoan Trypanosoma