Besides spreading Malaria, Anopheles mosquito's are also vectors of

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Correct — D, None of the above. Only three diseases appear anywhere in the option set, and exactly one of them is genuinely carried by Anopheles. Lymphatic filariasis is caused by the nematodes Wuchereria bancrofti, which accounts for about ninety per cent of cases, Brugia malayi and Brugia timori, and the World Health Organization's own description lists the transmitting mosquitoes as belonging largely to the genera Aedes, Anopheles, Culex and Mansonia — Anopheles is on that list, and is the principal filariasis vector across much of rural Africa, though in India the main vector of bancroftian filariasis is Culex quinquefasciatus. The other two diseases are not Anopheles-borne at all. Dengue is a flavivirus with four serotypes and is transmitted only by Aedes aegypti and Aedes albopictus. Japanese encephalitis is a separate flavivirus transmitted by Culex mosquitoes, principally Culex tritaeniorhynchus, with pigs as amplifying hosts and ardeid water birds as the natural reservoir. Now test each printed pair as printed. Option (a) pairs filariasis, which Anopheles does carry, with encephalitis, which it does not. Option (b) pairs filariasis with dengue, which it does not. Option (c) names dengue and encephalitis, neither of which it carries. Every pair therefore contains at least one disease that Anopheles does not transmit, no pair can be accepted whole, and the answer is 'None of the above'. This is a genuinely close call and honesty requires saying so: option (a) is the near miss, because it is half right where option (c) is entirely wrong, and the item reads like a pairs rewrite of the older single-answer question whose key was simply 'filariasis'. A setter working from that original might have intended (a). We answer as the options are printed, and as printed no pair survives. Note also that the stem prints 'Anopheles mosquito's' with an apostrophe; that is the Commission's own typography, reproduced here unaltered.

Why the other options are wrong — (a) Half right, and therefore the most dangerous option. Filariasis genuinely belongs on an Anopheles list. Encephalitis does not: Japanese encephalitis is spread by Culex tritaeniorhynchus and related Culex species of the vishnui group, which breed in irrigated rice fields and feed preferentially on cattle. A pair is accepted only if both halves hold, and this one fails on its first half.  (b) Also half right and fails the same test, but at the other end. Dengue is transmitted exclusively by Aedes aegypti and Aedes albopictus — day-biting, container-breeding, urban mosquitoes with white markings on the legs, an entirely different ecology from the night-biting Anopheles of the rural plains. Filariasis is the true half here, dengue the false one.  (c) The only option in which both halves are wrong. Dengue belongs to Aedes and Japanese encephalitis to Culex, so this pair names two diseases that Anopheles has nothing to do with. It is the option a candidate picks if they have simply memorised 'mosquito-borne diseases' as one undifferentiated list without attaching each to its genus.

Concept: 'Mosquito-borne' is not one category but four, and the whole of this topic is the mapping from genus to disease. ANOPHELES — malaria, caused by Plasmodium species and transmitted by the female Anopheles; in India the important vectors include Anopheles culicifacies in the rural plains and Anopheles stephensi in towns. Anopheles also transmits lymphatic filariasis in parts of the world. AEDES — dengue, chikungunya, yellow fever and Zika, all through Aedes aegypti and Aedes albopictus. CULEX — Japanese encephalitis, and in India the bulk of bancroftian filariasis through Culex quinquefasciatus. MANSONIA — brugian filariasis, breeding in water bodies choked with floating plants such as Pistia. The genera are told apart by behaviour as much as by markings: Anopheles rests with its body at an angle to the surface and its palps as long as the proboscis, while Culex and Aedes rest with the body roughly parallel; Anopheles lays its eggs singly with lateral floats, Culex in rafts, Aedes singly on damp surfaces above the water line. India's National Center for Vector Borne Diseases Control runs programmes against malaria, dengue, chikungunya, Japanese encephalitis, lymphatic filariasis and kala-azar — the last of which is not mosquito-borne at all but carried by the sandfly Phlebotomus argentipes, and is heavily concentrated in Bihar.

State PCS 2025 Q44 — Science & Technology PYQ with Answer

State PCS 2025 Q44 — Science & Technology PYQ with Answer