GRE Text Completion: JiJing 1373-GRE填空机经1373题 - L7O0KJXWDHT57HJJA

The ____________ of ophthalmology as a field in the United States from 1820 to 1850 is evident in the opening of at least five eye hospitals during this period, offering new venues for ophthalmic treatment and experimentation. A. sophistication B. retrenchment C. burgeoning D. resurgence E. curtailment F. expansion