A. Dot per inch
B. Dot per sq. inch
C. Dots printed per unit time
D. All of above

Solution

A. Dot per inch

Explanation

 In printing, DPI (dots per inch) refers to the output resolution of a printer or imagesetter, and PPI (pixels per inch) refers to the input resolution of a photograph or image. DPI refers to the physical dot density of an image when it is reproduced as a real physical entity, for example printed onto paper.