Final answer:
At temperatures above an organism's maximum growth temperature, the cell membrane becomes excessively fluid, and proteins can become permanently denatured due to broken hydrogen bonds, making choice E (A, B, and C are correct) the correct answer.
Step-by-step explanation:
At temperatures higher than the maximum growth temperature for an organism, several detrimental effects take place. The cell membrane becomes too fluid, which impairs its function, and proteins can become permanently denatured due to the disruption of their three-dimensional structure, mostly because the hydrogen bonds and other weak interactions that stabilize their structure are broken. Hence, answers A, B, and C are correct, making E the correct choice—A, B, and C are correct.