Hi akhi1996 & prateekchugh,
The issue here is ultimately about 'Exam security.' If you are reading out-loud, then you could potentially be recording content from the Test and/or asking someone for help. One of the direct ways to keep those issues from occurring is to make sure that Test-takers are NOT speaking out-loud. While it might be inconvenient to adjust your approach at this point (especially if you have been studying a certain way for some time), I'd like to believe that you are both capable of reading text without moving your lips or reading aloud. If you need time to get in the habit of working that way, then you might need to consider pushing back your At-home Test Date.
GMAT assassins aren't born, they're made,
Rich