The patient is breast fed, and his mother follows a vegan diet... On the basis of this information, the patient is at greatest risk for deficiency of which of the following vitamins?

Correct Answer: C

Rationale: Breastfed infants of vegan mothers risk vitamin B12 deficiency, as B12 is primarily in animal products, potentially causing anemia and neurological issues. B1 (A), B5 (B), and C (D) are available in plant-based diets.

Correct Answer: C

Rationale: The CDC and ACIP recommend that patients remain under observation for at least 15 minutes after vaccination to monitor for immediate adverse reactions, such as anaphylaxis, which is rare but can occur. This duration balances safety with practicality, as most serious reactions manifest within this timeframe. Choice A (60 minutes) and B (45 minutes) are excessively long for routine monitoring, while Choice D (10 minutes) is insufficient to catch all potential early reactions.

Correct Answer: D

Rationale: Measles is considered the most contagious vaccine-preventable disease, with a basic reproduction number (R0) of 12-18, meaning one infected person can infect 12-18 others in a susceptible population. It spreads via respiratory droplets and airborne transmission. Polio (R0 ~5-7), mumps (R0 ~4-7), and pertussis (R0 ~5-17) are also contagious but less so than measles, which has a higher attack rate and requires >90% vaccination coverage for herd immunity.

Correct Answer: B

Rationale: Clients have the right to refuse medical treatment, including vaccines, based on autonomy and bodily integrity (e.g., U.S. Patients’ Bill of Rights). However, healthcare providers should document the refusal in the client’s chart (Choice B) to record the discussion, education provided, and decision for legal and clinical continuity. Choice A is insufficient as it omits documentation, Choice C is inappropriate unless mandated by public health (e.g., outbreak), and Choice D, while part of education, is not the primary action.

Correct Answer: A

Rationale: B-Lymphocytes (B cells) are the white blood cells responsible for producing antibodies that bind to and neutralize antigens. Upon activation by antigens and helper T cells, B cells differentiate into plasma cells that secrete antibodies. Macrophages (Choice B) engulf pathogens, T-Lymphocytes (Choice C) include helper and cytotoxic types but don’t produce antibodies, and 'Cytotoxics' (Choice D) likely refers to cytotoxic T cells (CD8+), which kill infected cells, not produce antibodies.