<s>[INST] context: The infection is transmitted by the bite of the sandfly P.argentipes. The incubation period is usually from 2 to 6 months, though occasionally it may be as sho as 10 days oras long as two years. . The clinical illness begins with fever, which may be continuous, remittant or irregular. Splenomegaly stas early and is progressive and massive. Hepatomegaly and lymphadenopathy also occur but are not so prominent. The hair becomes thin and brittle. Epistaxis and bleeding gums are common. Most untreated patients die in about 2 years due to some intercurrent disease such as dysentery or tuberculosis. About 10 to 20 per cent of pateints who recover develop post kala-azar dermal leishmaniasis (PKDL). The dermal lesions usually develop about a year or two after recovery from the systemic illness. The lesions are of 3 types--depigmented macules which appear commonly on the trunk and extremities, or erythematous patches appearing on the face (butterfly patch), both of which develop into painless yellowish pink non-ulcerating granulomatous nodules. The parasite can be demonstrated in the lesions. [/INST] question: 40 year old male from Bihar complains of pain abdomen, having hepatosplenomegaly, peripheral smear on stain shows - | options: A: Plasmodium vivax B: Leishmania C: Microfilaria D: cryptosporidium parvum | answer: B </s>