Answer:
Natural selection
Explanation:
Natural selection is the main mechanism by which populations adapt and change over time to survive in their environment. Individuals in a population exhibit different gene variants or 'alleles' (i.e., individuals exhibit genetic variation). Some of these alleles are associated with phenotypic traits better suited to the environment than others. Natural selection can change allele frequencies in the population, increasing the frequency of the alleles associated with higher fitness, i.e., those alleles associated with lower mortality and the most offspring in a particular environment. Over time, these advantageous alleles become more common in the population. In consequence, natural selection can be considered as a statement on the expected value of allele frequencies under resampling from one generation to the next.
The major function of the large intestine is to absorb water. So i would go with two; reabsorption of fluids. Sorry if this is wrong.
The answer would be water.
23 points naisu anyways remember to post the qn lol