On which of the following grounds a woman married under Muslim Law shall be entitled to obtain a decree…

Section 2(i) of the Dissolution of Muslim Marriages Act, 1939 is the ground that "the whereabouts of the husband have not been known for a period of four years". Failure to provide maintenance is a ground under section 2(ii) only when it has lasted "for a period of two years", so a one-year failure is not enough.

As one of the two grounds is wrong, they cannot both be correct.