You can do this using the VBScript below. Doc Original.docx would be the original. Doc NoChanges.docx would be a document that matches doc A. Doc Changes.docx would be a doc that has changes from A.

Please note that Word has to be installed on the machine for this to work.

MyDoc1= ''C:MyDocsOriginal.docx''
MyDoc2= ''C:MyDocsNoChanges.docx'' 'no changes from Original.docx
'MyDoc2= ''C:MyDocsChanges.docx'' 'changes from Original.docx

set objWord = createobject(''Word.Application'')
objWord.Visible =true

Set oMyDoc1=objWord.Documents.Open(MyDoc1)
Set oMyDoc2=objWord.Documents.Open(MyDoc2)

Set Dcomp=objWord.CompareDocuments(oMyDoc1,oMyDoc2)

intChangeCount= Dcomp.Revisions.count

If intChangeCount <> 0 Then
'Some changes are detected
MsgBox ''There are changes''
Else
MsgBox ''There are no changes''
End If
oMyDoc1.Close
oMyDoc2.Close
Dcomp.Close false
objWord.Quit false
Set objWord=nothing