Solution:

Note writing could be a method of taking down the data given by another. it's drained an easy, understandable way such the most idea of the data is conveyed. Since it's taken quickly, it's not bound by grammatical rules. Detailed information isn't needed either.
Now, allow us to take a glance at the given options. One right statement and some wrong statements are given. we've got to decide on the right statement from the given options.
Option B is inaccurate as we don't must follow grammatical rules in note writing.
Option C is wrong as notes are alleged to be simple and to the purpose, not detailed.
Option A is that the correct statement as we should always make the note as quickly as possible and hence it must not have sentences.
Option D is wrong as we've an accurate statement, option A.