|Question 19Verbal

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For scientists to produce new iron nanoparticles of a specific size or strength, they must first be able to monitor reactions between oxygen and existing iron nanoparticles at a near-atomic level of detail. Fortunately, chemistry _______ and his colleagues at Temple University recently developed a new approach that does just that.
Which choice completes the text so that it conforms to the conventions of Standard English?
professor Yugang Sun
A
professor Yugang Sun,
B
professor, Yugang Sun
C
professor, Yugang Sun,
D