P: Those afflicted with a food allergy to MSG develop severe headaches after ingesting even small quantities of MSG;
P: Those not afflicted with the food allergy to MSG may suffer from a headache if they eat food containing a very large dose of MSG.
P: NOT adulterated MSG is flavorless, when present in the same dish with salt, it has a slight but distinct metallic aftertaste,
C: THEREFORE can alert the knowledgeable diner to its presence.
this stimulus is a mess....
If a person not afflicted with a food allergy to MSG suffers a
severe headache shortly after a restaurant dinner, what are the possible cause(s) of the headache:
A) very large amount of MSG in the dinner.
nope first premise talks about
eventual headhake not severe one
B) very large amount of MSG in the dinner, some unknown cause, or both.
seems the most plausible
C) very large amount of MSG mixed with salt in the dinner.
out of scope
D) very large amount of salt in the dinner.
not mentioned
E) metallic residue in the dinner
not mentioned in passage