TOEFL Listening: ETS-TOEFL听力机经 - AL5I5ONZ3DXE59G3P$

According to the professor, what is an important step for developers to take in designing easy-to-use computers? A. Determining the reasons that some computers are slow B. Becoming familiar with the design of currently existing computers C. Testing the new design for its compatibility with older systems D. Getting information from potential users early in the design process