Correct Answer: C

Rationale: The correct answer is 6 years old. At this age, children typically have the potential for 20/20 vision. This is considered the standard age for achieving optimal vision clarity. Choices A, B, and D are incorrect as they are not typically associated with the age at which children achieve 20/20 vision.

Correct Answer: C

Rationale: The correct answer is C. Patient confidentiality must be maintained at all times to respect the patient's privacy and dignity. Disclosing sensitive information like a patient's prognosis in a public setting violates confidentiality and can cause distress. The nurse should intervene in this situation and educate the nursing student about the importance of not discussing confidential patient information in public. Choices A, B, and D do not involve breaching patient confidentiality and do not require immediate nurse intervention. Choice A focuses on infection control measures, choice B relates to clinical assessment, and choice D is about the doctor's rounds, which are not urgent matters requiring immediate intervention.

Correct Answer: C

Rationale: Tuberculosis, caused by Mycobacterium tuberculosis, primarily affects the respiratory system. This aerobic bacillus thrives in highly oxygenated body sites, such as the lungs, growing ends of bones, and the brain. The bacillus is airborne, making the lungs a common site for infection. Choices A, B, and D are incorrect as tuberculosis predominantly impacts the respiratory system and rarely involves the stomach, heart, or skin.

Correct Answer: A

Rationale: For a blind patient scheduled for surgery the following morning, the best teaching strategy would be verbal teaching in short sessions throughout the day. Providing information in smaller amounts makes it easier to retain, and one-on-one teaching is most effective. Choice B, providing a pre-operative booklet in Braille, may not be as practical for last-minute teaching. Choice C, providing an audio recording, may not allow for immediate interaction and clarification. Choice D, having a family member instruct the patient, may not ensure the accuracy and clarity of the information provided.

Correct Answer: C

Rationale: The correct answer is C. HIV integrates its genetic material into the host cell's DNA. The virus uses the enzyme reverse transcriptase to make a DNA copy of its RNA, which is then inserted into the genetic material of the infected cell. Choice A is incorrect because the presence of antibodies does not indicate immunity to HIV but rather exposure to the virus. Choice B is incorrect as HIV replication occurs intracellularly, inside the host cell. Choice D is irrelevant to the characteristics of HIV.