Question

{"given":"Identify the hormone that regulates metamorphosis in insects.","key_observation":"Ecdysone (moulting hormone) is secreted by the prothoracic glands and specifically regulates metamorphosis in insects; pheromones are chemical communicators between organisms, not metamorphosis regulators, and thyroxine regulates amphibian metamorphosis.","option_analysis":[{"label":"(A)","text":"Pheromone","verdict":"incorrect","explanation":"Pheromones are chemical signals released by organisms to communicate with others of the same species; they do not regulate metamorphosis."},{"label":"(B)","text":"Thyroxine","verdict":"incorrect","explanation":"Thyroxine regulates metamorphosis in amphibians (e.g., tadpole to frog), not in insects, which is the primary context of this question."},{"label":"(C)","text":"Ecdysone","verdict":"correct","explanation":"Ecdysone is the moulting hormone secreted by the prothoracic glands in insects; it was first isolated in crystalline form in 1954 by Butenandt and Karlson and directly regulates insect metamorphosis."},{"label":"(D)","text":"All of these","verdict":"incorrect","explanation":"Since pheromone does not regulate metamorphosis, 'All of these' cannot be correct."}],"answer":"(C)","formula_steps":[]}