05 February 2014
If you applying for your exams during your articleship training period then should be attest/sign by your principle employer only(means by the Member of ICAI at where you undergoing of your articleship training period),Because of during articleship training period service certificate shall give by your principle employer only.
In case you already completed your articleship training period and submitted form 108 then you can make sign by any member of ICAI.
Based on the your wording i assuming you are appearing for CA Final exams in the last six months of articleship training period, so you should be attest your exam application by your principle member only.