单选题 The nurse is teaching a female client with osteoporosis about her prescribed diet. Which of the following foods is the best source of calcium?
A. 1 cup of low-fat yogurt.
B. 1 cup of skim milk.
C. 1 oz of cheddar cheese.
D. 1 cup of ice cream.

【正确答案】 A

【答案解析】One cup of low-fat yogurt contains 415 mg of calcium. One cup of skim milk has 302 mg of calcium. One ounce of cheddar cheese has 20 mg of calcium. One cup of ice cream has 176 mg of calcium.