The word "holistic" (Line 5, Para. 3) means

A．the digital counterparts of handwritten letters can be found
B．rules in the variations in handwritten letters are found
C．the influence of people's reading habits on writing is traced
D．sentences and words rather than letters are taken as a whole

A．The amount of such documents is huge and hard to read.
B．Handwriting differs greatly from person to person.
C．Handwritings have never got definite digital counterparts.
D．Less people are willing to read handwritings today.