Straight from Talent Q website.....
In this scenario (not clicking submit before time expires) you do not need to worry as your answer will be submitted. If you select an answer so that it appears in the 'Selected answer' box but do not click 'Accept and Continue', the assessment system will submit the answer on your behalf if the time runs out. Therefore by making a selection, this will count as your submitted answer.
Thank God because I did this for at least half a dozen.