Sound can be converted from the electrical energy inside a computer into the mechanical energy of soundwaves in air by using
an ADC.
sampling.
decoding.
a transducer.

a transducer

Explanation:

A transducer happens to be a device that is being used for converting one form of energy into another generally when converting the input energy to the output energy. And for the transduction to take place, the change of one form of energy also occurs, like the conversion of mechanical energy to the electrical energy and also from electrical energy to mechanical energy, and which is what is required here. Hence, the correct option here is the transducer.

difference where there's no picture?

1. entrepreneur.com

2. wikipedia