Which form of efficient market hypothesis support the argument that technical analysis does not give any abnormal profit?
Weak form.
Why not all the three forms
Yes: it’s hierarchical.
Anything excluded by weak-form is excluded by semistrong-form.
Anything excluded by semistrong-form is excluded by strong form.
I thought that you would know that. Sorry.
Weak form assumes all past market-based information (i.e. prices, volume, and patterns thereof) is already reflected in the price. Semi-strong form assumes that all publicly-available information (of which market-based info is obviously a component) is reflected in the price, and strong-form adds private information to the mix - it assumes ALL info (both public and private) is reflected in the price.
So, as Magician said, they’re heirarchical - semi strong-form efficient implies weak-form efficient, and strong from implies semi-strong-form efficient (and thererefore, weak form efficient).