Amotor neuron transmits the effect of a nerve impulse to the muscle fiber at a

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs

the answer would be d : p

the sun creates it's own light, also gives light and life to bunch of stuff like plants,animals,humans etc.photosyntesis is the process of making food which needs sun,water,nutrients etc.