A client in her 7th month of pregnancy has been complaining of back pain and wants to know what can be done to relieve it. Which of the following responses by the nurse is most effective（）
A. "You need to lie down more during the day to get off your feet. "
B. "Avoid lifting heavy loads, and try using the pelvic tilt exercise. "
C. "Have others pick things up for you so you don’t have to bend over so much. "
D. "Your back pain will go away after the baby is born. "