imo e
oa and source?

finance wrote:The AHA has documented that the fatty and highly processed foods of the basic American diet, along with the upsurge in smoking among women, were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that recent increases in smoking among teenage girls show that the fashion for healthier living has not entirely reversed the deleterious trends of a half-century ago.

A) were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that
B) that are the key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that
C) were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that
D) that is the key factor in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that
E) was a key factor in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that

OA E. Source: Princeton.

Why isn't it C? I thought that it should be C because it is 'foods...along with...'so it should be followed by WERE, or not?

The AHA has documented that the fatty and highly processed foods of the basic American diet, along with the upsurge in smoking among women,

The alongwith, in adddition to, etc acts as a modifier and do not change the subject. so the subject in this case is: the fatty and highly processed foods
Here fatty and highly processed describes foods
so basically the subject is: the foods

Because of MEANING of the sentence and The foods - One can see that it is A factor responsible for blah blah.. So use was

Thanks

finance wrote:OA E. Source: Princeton.

Why isn't it C? I thought that it should be C because it is 'foods...along with...'so it should be followed by WERE, or not?

Turns out OA is C! Please note this down everyone.

OE: Subject/Verb Agreement. "the fatty processed foods" is the subject. ("along with the upsurge.." is a prepositional phrase and therefore is not part of the subject".) We need a plural verb. The correct answer is C.

The AHA has documented that the fatty and highly processed foods of the basic American diet, along with the upsurge in smoking among women, were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that recent increases in smoking among teenage girls show that the fashion for healthier living has not entirely reversed the deleterious trends of a half-century ago.

A) were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that
B) that are the key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warn that
C) were key factors in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that
D) that is the key factor in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that
E) was a key factor in the increasing proportion of women who died from heart disease beginning in the 1950's, and warns that

Hello finance,

The OA IMOC.The subject of the main clause is AHA(an organisation),hence singular. This singular noun requires singular verbs "has documented" and "warns" .AND within the relative clause "foods" is the subject and requires the plural verb 'were'.