6-4 Sequential processing is characterized by

a. a pattern where partially completed units are worked on simultaneously.

b. a pattern where partially completed units must pass through one process before they can be worked on in later processes.

c. a pattern where different partially completed units must pass through parallel processes before being brought together in a final process.

d. a pattern where partially completed units must be purchased from outside suppliers and delivered to the final process in a sequential time mode.

e. None of these.