These days, impact printing such as that of a standard type writer has been replaced by high quality , high speed ink-jet printing . Its basic lies in building up of alphabets or figures by a jet of tiny liquid drops . Th negatively charged drops are guided by passing them between two conducing plates. A signal from a computer determines the charge on the drop. An electric field guides the drop to a particular position on the paper. About 100 tiny droplets are needed to form a single character.
The advantage of ink-jet printing over standard impact printing is

Options

A. Its high-speed
B. Its low cost
C. Simplicity of design
D. All of these

Answer

A