A 5-year-old boy who recently immigrated to Canada presents with no immunisation records. His parents are unsure which vaccines he has received. He is otherwise well. What is the most appropriate approach to his immunisations?AOrder serology for all vaccine-preventable diseases and tailor vaccines accordinglyBRestart a full age-appropriate immunisation schedule as if unimmunisedCGive no vaccines until records are obtained from his home countryDAdminister only tetanus and diphtheria vaccines until records are clarifiedEAdminister a single dose of MMR and assume prior vaccines are adequateCheck my answer