Correct Answer: D

Rationale: A pulse oximeter is used to detect the oxygen saturation levels in arterial blood before the onset of hypoxemia symptoms. This device provides essential information about the effectiveness of oxygen transportation to the body's tissues. Choice A is incorrect because a pulse oximeter does not directly measure hemoglobin levels nor determine the need for a blood transfusion. Choice B is incorrect because a pulse oximeter is designed specifically to assess oxygen saturation, not tissue perfusion. Choice C is incorrect because a pulse oximeter is not used to measure the efficacy of anti-hypertensive medications, but rather to monitor oxygen levels in the blood.

Correct Answer: C

Rationale: Acute Ear Infection is the correct answer because it typically refers to an infection that is short-lived and often severe, typically lasting less than 14 days. Chronic Ear Infection (Choice B) is incorrect as it refers to an ear infection that lasts for a long time or recurs often, typically more than three months. Mastoiditis (Choice A) is a complication of a middle ear infection and not an ear infection itself. Otitis Media (Choice D) is a general term for inflammation or infection in the middle ear, which can be either acute or chronic, so it's not specific enough to be the correct answer. Understanding the duration and severity of symptoms can help in identifying the type of ear infection, facilitating appropriate treatment and prevention of complications.

Correct Answer: A

Rationale: Critical incident stress management is a process that provides individuals with education about recognizing stress reactions and strategizing management techniques for handling stress after a disaster. Choice B, 'Follow-up', is incorrect because it generally refers to continuing care after initial treatment, not specifically to stress management education. Choice C, 'Debriefing', is a process where individuals involved in a critical event are brought together to discuss the event and their reactions to it. It can be part of the critical incident stress management process, but it doesn't cover the whole process. Choice D, 'Defusion', is a technique used in the immediate aftermath of a traumatic event to help individuals process their experiences, but it does not encompass the full range of education about stress recognition and management strategies.

Correct Answer: B

Rationale: The immunoglobulin passed from the mother to the child through the placenta is an example of natural passive immunity, making choice B the correct answer. This transfer gives the child temporary immunity to various diseases without their immune system having to work. On the other hand, natural active immunity (Choice A) occurs when the body produces its own antibodies in response to an antigen. Artificial active immunity (Choice C) is achieved through vaccinations, where the immune system is stimulated to produce antibodies against a specific disease. Artificial passive immunity (Choice D) is a temporary immunity that involves the transfer of pre-formed antibodies from another source.

Correct Answer: B

Rationale: The correct answer is B, as it emphasizes the importance of hygiene in food handling, which is crucial to prevent the spread of germs and diseases. The other options do not address the root of the issue, which is the unhygienic handling of food. Option A avoids direct confrontation but does not educate the vendor on proper hygiene. Option C, although it suggests a hygienic method, may not be practical or available in all situations. Option D is an avoidance strategy rather than a way to address the problem.