Which protozoa is responsible for causing the disease leucorrhoea?
A. Leishmania
B. Giardia
C. Trypanosoma
D. Trichomonas Vaginalis

Hint: The Leucorrhea is also caused by Trichomonas, which is a group of parasitic protozoa, especially Trichomonas vaginalis. The common symptoms of the disease are burning sensation, itching and discharge of foamy material, thick, white or yellow mucus.

Complete Answer:
1. Leishmaniasis: To parasitic disease caused by Leishmania. This parasite usually lives in infected sand flies. You can get leishmaniasis from the bite of an infected sand fly. Sand flies that carry parasites usually live in tropical and subtropical environments. The parasite of Leishmania is transmitted by the bite of an infected female benderella sand-fly, which feeds on blood to produce eggs.

2. Trypanosoma: The African trypanosomiasis or sleeping sickness is caused by the Trypanosoma Brucei parasite in sub-Saharan Africa and is spread by the tsetse fly. (Glossing). American trypanosomiasis or Chagas disease is caused by Trypanosoma craziness in Latin America and is spread by three atoms.

3. Giardia: The microscopic parasite that causes a diarrheal disease called Giardiasis. Giardia (also known as Giardia intestine, Giardia or Duodenum flagella) is found on surfaces or soil, food or water contaminated by the feces of infected humans or animals.

4. Trichomonas Vaginalis: A People can develop trichomoniasis for months without any symptoms. If you or your partner suddenly develop symptoms or test positive, it does not necessarily mean that someone is cheating. Any partner may have got it in the previous version.

Thus, the option (D) is correct.

Note: A Leucorrhea is also a sign of vaginitis (inflammation of the vagina), usually caused by infection by the fungus Candida albinos or by the protozoan parasite Trichomonas vaginalis. Infection with these organisms may cause irritating secretions, usually resistant to treatment.