posted by Angela .
Identify the sentence that is punctuated correctly.
A. The cost and size of computers decreased, as rapidly as processing power increased.
B. An operating system is the set of instructions, that directs the overall operations of the computer.
C. While database management systems have existed for some time, they were originally large, unwieldy, and difficult to use.
D. Changing careers, for people in later in life can be a positive experience.