Which statement compares how the euglena and volvox obtain food?

where is the option.let me know

the index of refraction of the second medium is higher. i just took the test trust me !

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.