Migraine, the most debilitating common form of headache, afflicts perhaps 18 million Americans, who collectively lose 64 million workdays a year, and they cost the nation $50 billion in medical expenses and lost work time.
A).year, and they cost the nation $50 billion in medical expenses and lost
B) year, and thus cost the nation $50 billion in medical expenses and lost
C) year, so as to cost the nation $50 billion in medical expenses and lost
D) year that costs the nation $50 billion in medical expenses and
E) year which thus cost the nation $50 billion in medical expenses and
WHy answer is B?? shouldnt it be " costs" rather than "cost"??
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