Correct Option: B

Vector for sleeping sickness is Tse-Tse fly (Glossina palpalis). The parasite Trypanosoma is transmitted through the bite of this fly. Tse-tse have been extensively studied because they are biological vectors of the African trypanosomiasis, deadly disease which includes sleeping sickness in people and nagana in cattle. Tse-tse have existed in the modern morphological form for at least 34 million years since fossil tse-tse have been recovered from the Florissant Fossil Beds in Colorado.