Foreign substances capable of causing disease are called:

Correct Answer: B

Rationale: Antigens are foreign substances (e.g., proteins on viruses or bacteria) that can trigger an immune response, potentially causing disease if pathogenic. Antibodies (Choice A) are produced by B cells to neutralize antigens. T-Lymphocytes (Choice C) and macrophages (Choice D) are immune cells that respond to antigens, not the substances themselves, making Choice B the correct term.

Correct Answer: C

Rationale: Anaphylaxis to a prior vaccine dose (Choice C) is a valid contraindication due to the risk of recurrence. Choice A (mild illness) is not a contraindication per CDC—vaccines can be given. Choices B and D (family circumstances) don’t affect the child’s eligibility unless the child is immunosuppressed.

Correct Answer: D

Rationale: Absolute contraindications to DTaP include a prior anaphylactic reaction (Choice B) due to risk of recurrence, and encephalopathy within 7 days of a prior dose without another cause (Choice C), per CDC, as these indicate severe risk. Moderate/serious illness (Choice A) is a precaution, not an absolute bar—vaccination is delayed until recovery. Choice D (B or C) captures both contraindications.

Correct Answer: B

Rationale: Preschoolers (3-5 years) are in Erikson’s Initiative vs. Guilt stage, exploring purpose. Trust vs. Mistrust (infancy), Identity vs. Role Confusion (adolescence), and Industry vs. Inferiority (school-age) don’t apply.

Correct Answer: B

Rationale: Poisoning is listed as the leading cause under 1 year in the document, though falls are more common per CDC (<1 year data). Assuming context (e.g., post-infancy), Choice B aligns with the answer provided.