The process of voltage control to limit the volume of liquid delivered is used in:

A.
laser printers.

B.
thermal printers.

C.
impact printers.

D.
inkjet printers.

Explanation:

http://www.embedded.com/design/prototyping-and-development/4403968/Designing-aliquid-level-control-delivery-system-for-use-in-medical—industrial-control-processes