Correct Answer - Option 2 : Many students are not genius.
All students are not genius.
i) Every students is not genius. → False (as it is possible but not definite)
ii) Many students are not genius. → True
iii) Many students are genius. → False (as it is possible but not definite)
iv) Every non-students is a genius. → False (as it is possible but not definite)
Hence, 'Many students are not genius.' is the correct answer.