Suppose there are 10 million part-time workers and 90 million full-time workers in an economy. 5 million of the part-time workers switch to full-time work. As a result, the ________.
A. number of part-time workers decreases to 5 million
B. number of full-time workers decreases to 85 million
C. number of part-time workers remains the same
D. number of full-time workers increases to 95 million