[单项选择]A New Method to Kill AIDS Virus _________(46). But researchers won’’t know for a year or more whether it will work, scientist David Ho told journalists here Wednesday for the Fourth Conference in Viruses and Infections. "This is a study that’’s in progress," said Ho, head of the Aaron Diamond AIDS Research Center, New York. The study involves 20 people who started combinations of anti-HIV drugs very early in the course of the disease, within 90 days of their infections. They’’ve been treated for up to 18 months. Four others have dropped out because of side effects or problems complying with the exacting drug system. The drugs have knocked the AIDS virus down to undetectable levels in the blood of all remaining patients. And, in the latest development, scientists have now tested lymph nodes (淋巴结) and semen (精液) from a few patients and found no virus reproducing there._________(47). Ho has calculated that the drugs should be able to wipe out remaining viruses—at