A student want to view live organisms less than 1 millimeters in size, which are found in a water sample collected from a stream. Which microscope would be best for the student to use while observing these living organisms?

i think that c)gold was found there

but i am not sure

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).