71. Dr. Edward's study shows that ____.

1. men with high levels of vitamin D would not suffer heart attack
2. men could benefit from sunshine to protect the heart
3. men with low vitamin D have a low risk for heart attack
4. men deficient in vitamin D are more vulnerable to cardiovascular disease

72. Vitamin D, according to the researches, ____.

1. can be gained by drinking a lot of milk
2. has the normal range between 15-30 nanograms per liter of blood
3. helps the body absorb sunlight and is good for bone growth
4. can protect against breast cancer, peripheral artery disease and tuberculosis

73. Vitamin D deficiency may lead to the following ailments except ____.

1. rickets
2. osteoporosis
3. stroke
4. diabetes

74. Giovannucci encourages people to ____.

1. go outside to enjoy sunshine
2. eat fatty fish like salmon
3. keep a normal level of vitamin D
4. take vitamin D supplements every day

75. From the passage we can learn that ____.

1. in the past vitamin D was just known to have bone effects
2. there are lots of methods to ensure the normal absorbing of vitamin D
3. vitamin D deficiency may change organs' functions in the long run
4. vitamin D levels are quite difficult to be measured by doctors

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