Q1. Which of the following is an invalid pair?
A Impact printers, Daisy wheel printers
B Line printers, Drum printers
C Page printers, Laser printers
D 132-column printers, Inkjet printers Correct
Explanation
Daisy wheel printers are impact printers because they strike characters through a ribbon onto paper. Drum printers are line printers, as they print a whole line using a rotating drum mechanism. Laser printers are commonly classified as page printers because they compose and print a full page image. A 132-column printer refers to wide-column printing, typically associated with line or dot-matrix style output, while inkjet printers are non-impact character or page printers and are not defined by 132-column line-printer classification. Hence the invalid pair is 132-column printers and inkjet printers.