Which of the following is a contraindication for immunizations in children?

Rationale: A. A low-grade fever is not a contraindication and children can usually still receive vaccines safely. B. A severe allergic reaction (anaphylaxis) to a previous dose of a vaccine or its components is a true contraindication and requires permanent avoidance of that specific vaccine. C. Mild respiratory illnesses without fever generally do not prevent vaccination. D. The common cold is not a reason to delay immunization unless the child is severely ill.