Which One of the Following Is the Primary Difference Between

Multiple Choice

Which one of the following is the primary difference between an anaphylactic reaction and an anaphylactoid reaction?

A) An anaphylactoid reaction may occur without prior sensitization to the antigen; anaphylaxis requires prior sensitization.
B) Anaphylactoid reactions are less severe than anaphylactic reactions.
C) Epinephrine is contraindicated in anaphylactoid reactions, but not in anaphylactic reactions.
D) Anaphylactoid reactions are commonly caused by environmental substances; anaphylactic reactions are most commonly caused by foods.