GRE Text Completion: Fundamental 24 Sets-GRE填空基础24套 - 6EE187I74YNPBM7N!

Scientific discoveries are often thought of as the result of (i)____________ effort, but many discoveries have, in fact, arisen from (ii)____________ or a mistake. A. incidental B. an accident C. systematic D. a method E. collaborative F. a mishap