Which of the following is an example of a confounding variable?

Correct Answer: C

Rationale: The correct answer is C because a confounding variable is a variable that affects both the independent and dependent variables, leading to a false association between them. This can result in misleading conclusions about the relationship between the variables of interest. In contrast, choice A is incorrect because a variable not measured in the study would not impact the relationship between the variables being studied. Choice B is incorrect because a variable manipulated by the researcher would be the independent variable, not a confounding variable. Choice D is incorrect because a variable that is kept constant would not introduce any confounding effects.

Correct Answer: B

Rationale: Rationale: 1. Vasoconstriction narrows blood vessels, increasing resistance to blood flow, leading to higher blood pressure. 2. Vasodilation widens blood vessels, reducing resistance, resulting in lower blood pressure. 3. Therefore, the statement that vasoconstriction lowers blood pressure and vasodilation elevates blood pressure is accurate. Summary: - Choice A is incorrect because it states the opposite of the correct relationship between vasoconstriction and blood pressure. - Choices C and D are irrelevant as they do not provide any information to support or refute the given statement.

Correct Answer: A

Rationale: The correct answer is A because isolating a sick person inside a private room helps prevent the spread of infectious diseases to others. By keeping the sick person in a separate room, it reduces the chances of transmitting the illness to those with robust immunity. This method is recommended in healthcare settings to contain outbreaks and protect vulnerable individuals. Choices B, C, and D are incorrect as they do not specifically address the need for physical separation to prevent the spread of illness.

Correct Answer: B

Rationale: The correct answer is B: Treat the bleeding first. In the case of a bone fracture where the bone is exposed to the skin and causes bleeding, it is crucial to address the bleeding as a priority to prevent excessive blood loss and potential complications. By treating the bleeding first, you can stabilize the patient's condition and reduce the risk of shock. Immobilizing the bone is important but secondary to controlling the bleeding. Choice C and D are incorrect as they do not address the immediate concern of managing the bleeding in this scenario.

Correct Answer: A

Rationale: The correct answer is A: Constipation. Constipation refers to the passage of small, dry, hard stools due to difficulty in bowel movements. It is a common condition that can be caused by various factors such as inadequate fiber intake, dehydration, or lack of physical activity. In contrast, fecal impaction (choice B) is a more severe condition where a large mass of dry, hard stool gets stuck in the rectum and cannot be passed easily. Choices C and D are incorrect as they are not relevant to the description provided in the question.