The diagrams show different types of bonds found in biological molecules. Which combination of bonds could not be found in a protein with a tertiary structure? A. 1, 2, 3, and 4
B. 1, 2, and 4 only
C. 3 and 5
D. 5 only

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.