no one can predict exactly that what will be the marking trend of psychology or any other subject in the upcoming years.

You can get good marks in psychology provided with proper preparation and best presentation in the paper.
Remember,
only preparation is not enough. 3 hours of paper or most important period for getting good marks in any paper. Any person can get good marks with average preparatin if he performs well in that 3 hours and a person with best preparation could not be able to get good marks if he does not perform well in that 3 hours. So one should 1st of all prepare well and then perform well in the 3 hours of paper to get good marks.

Indo pak was low scoring in the previous years but some people got 130+ in that years due to their presentation in the paper.
Geography was a good scoring subject and some candidates got below 100 marks in geography due to their improper presentation.

I hope you got my point.
Now prepare well and Allah will surely help you and you will get good marks.

Wishing you best of luck

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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.