To this day many Chinese doctors continue to use
to help their patients.

Vaccine

Explanation: Since SARS-CoV-2 was first reported in China almost a year ago, policymakers have swung the weight of the state’s resources towards developing a vaccine. Their approach, alongside similar efforts in other countries, has thrown a spotlight on immunology, epidemiology and virology, bringing increased funding, prestige and public interest.

D. He hired the oldest workers because they had the most wisdom.

Explanation:

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