Correct Answer: B

Rationale: The correct answer is B: Mashed potatoes and broiled chicken. Both mashed potatoes and broiled chicken are typically low in sodium content, making them suitable choices for a 500-mg low sodium diet. The other options, such as a ham and Swiss cheese sandwich on whole wheat bread, a tossed salad with oil and vinegar and olives, and chicken bouillon, may contain higher amounts of sodium and are not typically recommended for a low sodium diet.

Correct Answer: B

Rationale: Body hair plays an active role in preventing infection by acting as a filter to block pathogens. It helps to prevent harmful substances from entering the body through the skin, providing a physical barrier against potential infections.

Correct Answer: A

Rationale: Penicillin can be administered intramuscularly or intravenously.

Correct Answer: A

Rationale: Caffeine is a diuretic, which means it increases urine production by promoting the excretion of water from the body through the kidneys. Therefore, substances like caffeine-containing drinks, such as coffee and cola, can lead to an increase in the amount of urine produced.

Correct Answer: A

Rationale: Leukopenia, characterized by low white blood cell count, significantly reduces the body's ability to fight infections. Patients with leukopenia are at a higher risk of contracting infections due to compromised immune defenses.