Which of the following is NOT a ground of pre-grant opposition u/s 25(1)?

Section 25(1) of the Patents Act, 1970 lists the grounds of pre-grant representation in clauses (a) to (k), including anticipation by prior publication, that the subject of a claim "is not an invention" or is not patentable, and failure to disclose the information required by section 8. Clause (g) covers a specification that "does not sufficiently and clearly describe the invention", but unclear claims as such are not a listed ground; that is a ground of revocation under section 64(1)(i).