The hydrogen atom of one water molecule bonds with the oxygen atom of another water molecule. what is this bond referred to as? 1hydrogen bond 2covalent bond 3ionic bond

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.