A client who is 7 months pregnant reports severe leg cramps at night. Which nursing action would be most effective in helping her cope with these cramps（）
A. Suggesting that she walk for 1 hour twice per day.
B. Advising her to take over-the-counter calcium supplements twice per day.
C. Teaching her to dorsiflex her foot during the cramp.
D. Instructing her to increase milk and cheese intake to 8 to 10 servings per day.
