Scientists (主詞) c☆☆☆☆☆(★★) ...
還原成原句是:Scientists who are called virologists study viruses to discover how they work and how to stop people from getting them.
減化後為:Scientists called virologists study viruses to discover how they work and how to stop people from getting them.
(D)錯在少了be動詞
22. Scientists ________ virologists stud..-阿摩線上測驗