Correct Answer: A

Rationale: The correct answer is A. Alendronate should be taken with a full glass of water and patients should remain upright for at least 30 minutes to prevent esophageal irritation and ensure proper absorption. Taking the medication with milk (choice B) is not recommended as it may interfere with the absorption of alendronate. Taking the medication at bedtime (choice C) is not necessary for optimal absorption. Taking the medication with food (choice D) is also not recommended as food can reduce the absorption of alendronate.

Correct Answer: A

Rationale: The correct instruction for the nurse to include in this patient's health education regarding chloroquine phosphate (Aralen) for malaria prophylaxis is to "Take your pill on the same day each week." This is essential because chloroquine is typically taken once a week on the same day to ensure consistent protection against malaria. Choice B is incorrect because while rashes are a possible side effect of chloroquine, they are not a usual occurrence and should be reported to the healthcare provider. Choice C is incorrect because chloroquine does not need to be taken on an empty stomach. Choice D is incorrect as chloroquine is typically administered orally, not by injection.

Correct Answer: C

Rationale: In this scenario, a decubitus ulcer on the coccyx indicates a breakdown of the skin's integrity due to prolonged pressure. The skin is the primary defense mechanism of the body against external pathogens. When the skin is compromised, it can lead to infections and other complications. The mucous membrane (Choice A) plays a role in protecting internal surfaces, not the skin. The respiratory tract (Choice B) is involved in breathing and not directly related to the skin's defense. The gastrointestinal tract (Choice D) is responsible for digestion and absorption of nutrients, not the primary defense mechanism against external threats like the skin.

Correct Answer: C

Rationale: IgM is the first immunoglobulin to challenge the antigen during an immune response. IgM is the primary antibody produced during the initial or primary immune response. It is efficient in agglutination and complement activation, making it crucial in the early stages of defense. IgA is mainly found in mucosal areas and secretions. IgG is the most abundant antibody in circulation and is involved in secondary immune responses. IgE is primarily associated with allergic reactions and parasitic infections. Therefore, IgM is the correct choice as it acts first during the immune response, while the other immunoglobulins have different roles and functions.

Correct Answer: C

Rationale: The correct answer is C: Special visceral afferent cells. These cells are responsible for innervating taste and smell receptors related to the gut. Special somatic afferent fibers (choice A) are involved in sensations like touch and proprioception, not taste and smell. General somatic afferents (choice B) carry sensory information from the skin and musculoskeletal system, not taste and smell. General visceral afferent neurons (choice D) transmit sensory information from internal organs, but not specifically related to taste and smell sensations.