Option A: 'Scan' means 'to look at the parts of something carefully to acknowledge all the relevant information'. It is relevant to the sentence, and hence forms a complete thought:
It is a good practice to study/scan the document and make sure that everything is correct, before sending it for publication'.
Hence option A is correct.
Option B: 'Peer' means 'to look with difficulty at something'.
Option C: 'Look up' means 'to search for something'.
Option D: 'See' means 'to perceive through the eyes'.
These words do not provide the required meaning: to study the document before sending it for publication.
Hence options B, C and D are incorrect.