he physical and cognitive suffering that may cause a drug user to relapse after trying to quit is called . A. addiction B. tolerance C. chronic usage D. withdrawal Please select the best answer from the choices provided A B C D

Which of the following statements is accurate in describing the activity of the lactase enzyme? a. lactase can function equally effectively at many different ph levels b. the shape of lactase does not change during the reaction c. lactase is converted to glucose and galactose by the reaction d. one lactase enzyme can catalyze many reactions