Which of the following is an example of specialization?

A.

The cost of production of a light bulb making factory decreasing as its capacity increased

B.

Different workers in a shoe factory being allotted different parts of shoe making instead of a worker making an entire shoe

C.

The import of better technology and machinery from developed countries greatly increasing the number of laser printers manufactured by a company

D.

The output of workers in a chocolate factory doubling when a new manager was appointed