Which grouping has the least complex body plan? if you were on a research expedition in the kingdom of tonga, a coral atoll in the south pacific, would you find these organisms?

is this a psat question, if so do not cheat try your best.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.