Which of the following most logically completes the argument?

A new drug, taken twice daily for one month, is an effective treatment for a certain disease. The drug now most commonly prescribed for the disease occasionally has serious side effects such as seizures; in field tests, the new drug’s side effects, though no worse than mild nausea, turned out to be much more frequent. Nevertheless, the new drug is clearly preferable as a treatment, since _____.

A. people who experience nausea are prone to discontinue use of the new drug prematurely

B. …

C. …

D. …

E. there is a nonprescription medication that when taken with the new drug prevents the onset of nausea

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