Correct Answer: D

Rationale: The correct answer is 'D: lack of exposure to sunlight.' Older adults, especially those in assisted living communities, are at risk of vitamin D deficiency due to spending most of their time indoors, which reduces their exposure to sunlight. Sunlight is essential for the body to produce vitamin D. Choices A, B, and C are less likely to be major factors in compromising vitamin D status. While a decreased intake of fruits and vegetables and lack of physical activity can impact overall health, they are not as directly related to vitamin D status. Malabsorption due to atrophic gastritis may affect the absorption of certain nutrients, but vitamin D synthesis primarily depends on sunlight exposure.

Correct Answer: A

Rationale: The correct answer is A: hemoglobin. Hemoglobin is the protein found in red blood cells that is responsible for carrying oxygen from the lungs to the rest of the body. Iron is a crucial component of hemoglobin, binding to oxygen and allowing for its transport. Choice B, transferrin, is involved in iron transport in the blood but not in oxygen transport. Choice C, myoglobin, is a protein found in muscle cells that stores oxygen for muscle use, not transportation in the bloodstream. Choice D, hepcidin, is a peptide hormone that regulates iron absorption in the intestines and iron distribution in the body, but it is not directly involved in oxygen transport.

Correct Answer: D

Rationale: Type 2 diabetes is characterized by insulin resistance, high blood glucose levels, and high blood insulin levels. Rapid destruction of the pancreas is not a feature of this condition. The destruction of pancreatic beta cells is more commonly associated with type 1 diabetes, not type 2 diabetes. Therefore, option D is the correct answer. Options A, B, and C are all characteristic features of type 2 diabetes, making them incorrect choices.

Correct Answer: B

Rationale: Acupuncture is a key practice in traditional Chinese medicine. It involves the insertion of thin needles into specific points on the body to balance energy flow and promote healing. Magnet therapy, faith healing, and biofeedback are not specifically associated with traditional Chinese medicine practices.

Correct Answer: A

Rationale: High blood pressure, or hypertension, is typically defined as having a systolic pressure of 140 mm Hg or higher and/or a diastolic pressure of 90 mm Hg or higher. Therefore, the correct answer is A. Choice B is incorrect because it suggests a higher systolic measurement than the standard definition. Choice C is incorrect as it provides an even higher systolic measurement and a much higher diastolic measurement. Choice D is also incorrect as it suggests extremely elevated blood pressure values, well above the typical definition of hypertension.