I dont agree that any subject is high or low scoring.However it is one's own aptitude in particular faculty which earns him or her more marks.It is full of fallacy to assume that if one takes Physics as one of the optional subjects he will earn low score and if he takes Islamic History and Culture he will get high score.These are fictitious thinkings that there exists any trend of low and high markings in Fpsc policy making.These are just mind boggling assesments of aspirants on inaccurate data,which is not reliable.
The examiner,who checks papers, is not just expert in assesment of papers but encompasses innumerable and undeniable grip and command on subject,he is assesing.Therefore, one should workhard instead of indulging into blame tirade.Because hard work is only reliable instrument that can earn you ,your spur.
BEST REGARDS.