the markers wont know what your school did, so technically you can!
BUT
i know a few people who didnt do their own option(last yr) cause they didnt know how to answer it, and an option they hadnt studied looked easier, but they didnt end up doing well anyway!
for your own option u know the specific criteria which needs to be written, not just the general knowledge that you could probably use to answer most of the questions but it wouldnt get u very far!!
eg. if ur asked specifically on children athletes, and it wasnt ur option, u would prob go into stuff like, their prone to accidents and injury.... blah, blah,blah.
and u wouldnt know to specifically focus on diabetes, asthma, epilspsy, thermoregulation.......and so on.
basically what i'm trying to say is- DONT CHANGE YOUR OPTION!!!!!!
well good luck all.
WE'RE GONNA DO GREAT!!! MUAH XOXO